To understand the relationship between planktonic diatoms and environmental variables in the lakes on the Songnen Plain,northeast(NE)China,we investigated water quality and planktonic diatoms from 71 sampling points i...To understand the relationship between planktonic diatoms and environmental variables in the lakes on the Songnen Plain,northeast(NE)China,we investigated water quality and planktonic diatoms from 71 sampling points in 27 lakes,based on which Canonical Correspondence Analysis(CCA)was conducted.The result show that planktonic diatoms displayed certain responses to environment gradients,and the total phosphorus(TP)explained the maximum variation of planktonic diatom species among the 15 environmental variables,suggesting that TP was the most important and significant environmental parameter affecting the distribution of diatom species.In addition,we established a diatom-total phosphorus transfer(DTPT)function,of which component 5 of the weighted averaging partial least squares regression(WAPLS)was chosen to and compared with a series of weighted average regression(WA)models and WA-PLS models.According to the jackknifing statistical test,the component 5 of WA-PLS models provided a lower root-mean-square error prediction(RMSEP=0.202)and a higher correlation coefficient between observation and prediction(R^2_Jack=0.759).After deletion of three outliers,the root-mean-square error prediction of the DTPT function was reduced(RMSEP=0.169)while the correlation coefficient between observation and prediction was increased(R^2_Jack=0.823).Therefore,this DTPT function performed better than other regional TP models in the world.However,it remains demanding for expanding the background dataset to improve the prediction ability of the model.展开更多
The effluent total phosphorus(ETP) is an important parameter to evaluate the performance of wastewater treatment process(WWTP). In this study, a novel method, using a data-derived soft-sensor method, is proposed to ob...The effluent total phosphorus(ETP) is an important parameter to evaluate the performance of wastewater treatment process(WWTP). In this study, a novel method, using a data-derived soft-sensor method, is proposed to obtain the reliable values of ETP online. First, a partial least square(PLS) method is introduced to select the related secondary variables of ETP based on the experimental data. Second, a radial basis function neural network(RBFNN) is developed to identify the relationship between the related secondary variables and ETP. This RBFNN easily optimizes the model parameters to improve the generalization ability of the soft-sensor. Finally, a monitoring system, based on the above PLS and RBFNN, named PLS-RBFNN-based soft-sensor system, is developed and tested in a real WWTP. Experimental results show that the proposed monitoring system can obtain the values of ETP online and own better predicting performance than some existing methods.展开更多
Several methods for analysis of dissolved total phosphorus in seawater were reviewed. Discussions were focused on UVirradiation and persulphate oxidation methods which are the most popular dissolved organic phosphorus...Several methods for analysis of dissolved total phosphorus in seawater were reviewed. Discussions were focused on UVirradiation and persulphate oxidation methods which are the most popular dissolved organic phosphorus determinationmethods presently. The compounds used for the phosphorus recovery test were categorized into three groups accordingto their chemical structure. It was found that low power UV irradiation can decompose POC or PC bonds efficientlybut may be inefficient for POP bonds. Heating-bath in acid condition is useful for decomposing POP bonds. Usingthe continuous flow analysis system (Auto-analyzer II), UV digestion and heating-bath, series experiments were carriedout based on the above analysis. Eleven model compounds were employed for the phosphorus recovery test and thefactors influencing the decomposition efficiency of dissolved compounds containing phosphorus were clarified. Finally,the optimal design for determination of dissolved total phosphorus in seawater based on the routine continuous flowanalysis system was presented. For the organic mono-phosphate, the recovery is more than 90% and a recovery of33%~51% was obtained for inorganic or organic polyphosphates. Up to now, this is the highest decompositionefficiency for dissolved phosphorus based on the continuous flow analysis system.展开更多
For some hundred surface sediment samples from five cores taken in two cruises near the Huanghe River Estuary, total phosphorus (TP (.inorganic phosphorus (IP (and organic phosphorus (OP)were determined.On the average...For some hundred surface sediment samples from five cores taken in two cruises near the Huanghe River Estuary, total phosphorus (TP (.inorganic phosphorus (IP (and organic phosphorus (OP)were determined.On the average, 527×10-6, 455×10~6 and 72×10-6 were found for TP,IP and OP for the surface sediments taken in the two cruises. The distribution of OP and IP was controlled by the sample particle size: OP content increased with the decreasing of the sample particle size, while the maximal value of IP was found in the silt fraction due to the existence of apatite in our samples. Vertical distributions reflected well the channel change of the Huanghe River. Results from the multiple regressions between the three forms of phosphorus and the percentages of different particle size agreed well with the analytical data.展开更多
Although abundant research on the anisotropy of van der Waals(vd W)materials has been published,we undertake an in-depth study of their optical properties as they have an important guiding role for light control in tw...Although abundant research on the anisotropy of van der Waals(vd W)materials has been published,we undertake an in-depth study of their optical properties as they have an important guiding role for light control in two-dimensional(2D)nanospace.As an example,we study the reflectance of few-layered black phosphorus(BP)in the total internal reflection(TIR)mode in detail.We demonstrate that its optical anisotropy can be changed on a large scale by varying the incident angles,polarization states,and the in-plane rotation angles of the BP samples.Theoretical analysis indicates that the phenomena observed are common to all the atom-thick biaxial crystals,so these conclusions can be widely applied to other anisotropic 2D materials.This research furthers the current understanding of the properties of BP more comprehensively,and provides guidance for developing new optoelectronic applications,especially when BP and other atom-thick biaxial crystals are integrated with TIR devices.展开更多
The study was conducted to investigate the effect of Rhizobium inoculation and supplementation of phosphorus and potassium on growth and total leaf chlorophyll content to the three released bush bean varieties in nort...The study was conducted to investigate the effect of Rhizobium inoculation and supplementation of phosphorus and potassium on growth and total leaf chlorophyll content to the three released bush bean varieties in northern Tanzania. To achieve this aim, the glasshouse experiment was conducted at Nelson Mandela African Institution of Science and Technology while field experiment were carried out at Tanzania Coffee Research Institute, in Kilimanjaro, Tanzania between April-July 2014. The experiment was laid out in factorial arrangement. Factor I comprised of three bush bean varieties. Factor II involved two inoculation treatments viz 1) inoculation with Rhizobium spp. and 2) without inoculation. Factor III included four fertilizer levels (0 Kg·ha-1 20 Kg K ha-1, 30 Kg P ha-1 and 20 kg·K + 30 Kg P ha-1). Both screen house and field experiments were replicated four times. Plant growth parameters (plant height (cm), number leaves per plant, stem girth (mm)) were measured at 2, 4 and 6 weaks after planting (WAP). The chlorophyll was extracted by using Dimethylsulphoxide (DMSO) and absorbance was determined at 645 and 663nm using UV/Visible spectrophotometer. Results showed that Rhizobium application significantly improved the number of leaves per plant, plant height, pant girth and total leaf chlorophyll content. Furthermore, compared with the zero treatment control, potassium fertilization significantly increased the number of leaves per plant, plant height, pant girth and total leaf chlorophyll content of the three varieties. In general, these parameters were significantly increased with phosphorus supplied at 30 kg/ha. The combination of these supplies at different levels resulted in significant interactions in some parameters and thus indicating need for these inputs in the study area.展开更多
Total phosphorus is an important index in the monitoring of water quality, but the existing detection methods waste time and energy during the process of di- gestion. In this paper, the existing detection technology o...Total phosphorus is an important index in the monitoring of water quality, but the existing detection methods waste time and energy during the process of di- gestion. In this paper, the existing detection technology of total phosphorus and the digestion technology of organic phosphorus in the determination of total phosphorus were summarized firstly, of which photocatalytic degradation technology, as one of new technologies of organic phosphorus digestion, was introduced. Afterwards, tita- nium dioxide photocatalytic technology and its application were summarized, and its application prospects were expected.展开更多
Effects of conservation methods of water samples on determination of total phosphorus were analyzed from aspects of methods of adding conserving agent, SS concentration, natural sedimentation time, conservation temper...Effects of conservation methods of water samples on determination of total phosphorus were analyzed from aspects of methods of adding conserving agent, SS concentration, natural sedimentation time, conservation temperature and time. The results showed that SS concentration in water and natural sedimentation time had the greatest impact on the determination of total phosphorus, while the influence of methods of adding conserving agent, conservation temperature and time was relatively smaller. TP concentration in water samples conserved irregularly was higher than the standard value due to the existence of SS and microorganisms in water, and the deviation became larger with the increase of SS concentration in water. In addition, quality control measures and matters needing attention during the conservation process of water samples were put forward to improve the accuracy of TP concentration.展开更多
Harnessing the rhizospheric microbiome,including phosphorus mineralizing bacteria(PMB),is a promising technique for maintaining sustainability and productivity in intensive agricultural systems.However,it is unclear a...Harnessing the rhizospheric microbiome,including phosphorus mineralizing bacteria(PMB),is a promising technique for maintaining sustainability and productivity in intensive agricultural systems.However,it is unclear as to which beneficial taxonomic group populations in the rhizosphere are potentially associated with the changes in soil microbiomes shifted by fertilization regimes.Herein,we analyzed the diversity and community structure of total bacteria and PMB in the rhizosphere of maize(Zea mays L.)grown in soils under 25 years of four fertilization regimes(compost,biocompost,chemical,or nonfertilized)via selective culture and Illumina sequencing of the 16S rRNA genes.Plant development explained more variations(29 and 13%,respectively)in the composition of total bacteria and PMB in the rhizosphere of maize than the different fertilization regimes.Among those genera enriched in the rhizosphere of maize,the relative abundances of Oceanobacillus,Bacillus,Achromobacter,Ensifer,Paracoccus,Ramlibacter,and Luteimonas were positively correlated with those in the bulk soil.The relative abundance of Paracoccus was significantly higher in soils fertilized by compost or biocompost than the other soils.Similar results were also observed for PMB affiliated with Ensifer,Bacillus,and Streptomyces.Although plant development was the major factor in shaping the rhizospheric microbiome of maize,fertilization regimes might have modified beneficial rhizospheric microbial taxa such as Bacillus and Ensifer.展开更多
Based on previous studies,the effects of the type,content,particle size and state of sediment on the determination of total phosphorus in water are analyzed.The results show that the type of sediment has a certain inf...Based on previous studies,the effects of the type,content,particle size and state of sediment on the determination of total phosphorus in water are analyzed.The results show that the type of sediment has a certain influence on the determination result of total phosphorus,and the influence cannot be ignored.The degree of influence depends on the specific type.Sediment content is negatively correlated with the determination result of total phosphorus in water.That is,the higher the sediment content is,the lower the determination result is.The particle size of sediment is positively correlated with the determination result of total phosphorus in water.That is,the larger the particle size of sediment is,the higher the determination result is.Among the static,semi-suspended and completely suspended states,the sediment in the static state has the least impact on the determination of total phosphorus,and it has the greatest impact on the determination of total phosphorus when it is fully suspended.Therefore,in the analysis and testing process of total phosphorus,attention should be paid to the impact of sediment to improve the authenticity of the test results.展开更多
BACKGROUND Total hip arthroplasty is as an effective intervention to relieve pain and improve hip function.Approaches of the hip have been exhaustively explored about pros and cons.The efficacy and the complications o...BACKGROUND Total hip arthroplasty is as an effective intervention to relieve pain and improve hip function.Approaches of the hip have been exhaustively explored about pros and cons.The efficacy and the complications of hip approaches remains inconclusive.This study conducted an umbrella review to systematically appraise previous meta-analysis(MAs)including conventional posterior approach(PA),and minimally invasive surgeries as the lateral approach(LA),direct anterior approach(DAA),2-incisions method,mini-lateral approach and the newest technique direct superior approach(DSA)or supercapsular percutaneouslyassisted total hip(SuperPath).AIM To compare the efficacy and complications of hip approaches that have been published in all MAs and randomized controlled trials(RCTs).METHODS MAs were identified from MEDLINE and Scopus from inception until 2023.RCTs were then updated from the latest MA to September 2023.This study included studies which compared hip approaches and reported at least one outcome such as Harris Hip Score(HHS),dislocation,intra-operative fracture,wound compliData were independently selected,extracted and assessed by two reviewers.Network MA and cluster rank and surface under the cumulative ranking curve(SUCRA)were estimated for treatment efficacy and safety.RESULTS Finally,twenty-eight MAs(40 RCTs),and 13 RCTs were retrieved.In total 47 RCTs were included for reanalysis.The results of corrected covered area showed high degree(13.80%).Among 47 RCTs,most of the studies were low risk of bias in part of random process and outcome reporting,while other domains were medium to high risk of bias.DAA significantly provided higher HHS at three months than PA[pooled unstandardized mean difference(USMD):3.49,95%confidence interval(CI):0.98,6.00 with SUCRA:85.9],followed by DSA/SuperPath(USMD:1.57,95%CI:-1.55,4.69 with SUCRA:57.6).All approaches had indifferent dislocation and intraoperative fracture rates.SUCRA comparing early functional outcome and composite complications(dislocation,intra-operative fracture,wound complication,and nerve injury)found DAA was the best approach followed by DSA/SuperPath.CONCLUSION DSA/SuperPath had better earlier functional outcome than PA,but still could not overcome the result of DAA.This technique might be the other preferred option with acceptable complications.展开更多
The crossmodal interaction of different senses,which is an important basis for learning and memory in the human brain,is highly desired to be mimicked at the device level for developing neuromorphic crossmodal percept...The crossmodal interaction of different senses,which is an important basis for learning and memory in the human brain,is highly desired to be mimicked at the device level for developing neuromorphic crossmodal perception,but related researches are scarce.Here,we demonstrate an optoelectronic synapse for vision-olfactory crossmodal perception based on MXene/violet phosphorus(VP)van der Waals heterojunctions.Benefiting from the efficient separation and transport of photogenerated carriers facilitated by conductive MXene,the photoelectric responsivity of VP is dramatically enhanced by 7 orders of magnitude,reaching up to 7.7 A W^(−1).Excited by ultraviolet light,multiple synaptic functions,including excitatory postsynaptic currents,pairedpulse facilitation,short/long-term plasticity and“learning-experience”behavior,were demonstrated with a low power consumption.Furthermore,the proposed optoelectronic synapse exhibits distinct synaptic behaviors in different gas environments,enabling it to simulate the interaction of visual and olfactory information for crossmodal perception.This work demonstrates the great potential of VP in optoelectronics and provides a promising platform for applications such as virtual reality and neurorobotics.展开更多
BACKGROUND There is concern regarding potential long-term cardiotoxicity with systemic distribution of metals in total joint arthroplasty(TJA)patients.AIM To determine the association of commonly used implant metals w...BACKGROUND There is concern regarding potential long-term cardiotoxicity with systemic distribution of metals in total joint arthroplasty(TJA)patients.AIM To determine the association of commonly used implant metals with echocardiographic measures in TJA patients.METHODS The study comprised 110 TJA patients who had a recent history of high chromium,cobalt or titanium concentrations.Patients underwent two-dimensional,three-dimensional,Doppler and speckle-strain transthoracic echocardiography and a blood draw to measure metal concentrations.Age and sex-adjusted linear and logistic regression models were used to examine the association of metal concentrations(exposure)with echocardiographic measures(outcome).RESULTS Higher cobalt concentrations were associated with increased left ventricular end-diastolic volume(estimate 5.09;95%CI:0.02-10.17)as well as left atrial and right ventricular dilation,particularly in men but no changes in cardiac function.Higher titanium concentrations were associated with a reduction in left ventricle global longitudinal strain(estimate 0.38;95%CI:0.70 to 0.06)and cardiac index(estimate 0.08;95%CI,-0.15 to-0.01).CONCLUSION Elevated cobalt and titanium concentrations may be associated with structural and functional cardiac changes in some patients.Longitudinal studies are warranted to better understand the systemic effects of metals in TJA patients.展开更多
BACKGROUND Total knee arthroplasty(TKA)is a mature procedure recommended for correcting knee osteoarthritis deformity,relieving pain,and restoring normal biomechanics.Although TKA is a successful and cost-effective pr...BACKGROUND Total knee arthroplasty(TKA)is a mature procedure recommended for correcting knee osteoarthritis deformity,relieving pain,and restoring normal biomechanics.Although TKA is a successful and cost-effective procedure,patient dissatisfaction is as high as 50%.Knee pain after TKA is a significant cause of patient dissatisfaction;the most common location for residual pain is the anterior region.Between 4%and 40%of patients have anterior knee pain(AKP).AIM To investigate the effect of various TKA procedures on postoperative AKP.METHODS We searched PubMed,EMBASE,and Cochrane from January 2000 to September 2022.Randomized controlled trials with one intervention in the experimental group and no corresponding intervention(or other interventions)in the control group were collected.Two researchers independently read the title and abstract of the studies,preliminarily screened the articles,and read the full text in detail according to the selection criteria.Conflicts were resolved by consultation with a third researcher.And relevant data from the included studies were extracted and analyzed using Review Manager 5.4 software.RESULTS There were 25 randomized controlled trials;13 were comparative studies with or without patellar resurfacing.The meta-analysis showed no significant difference between the experimental and control groups(P=0.61).Six studies were comparative studies of circumpatellar denervation vs non-denervation,divided into three subgroups for meta-analysis.The two-subgroup meta-analysis showed no significant difference between the experimental and the control groups(P=0.31,P=0.50).One subgroup meta-analysis showed a significant difference between the experimental and control groups(P=0.001).Two studies compared fixed-bearing TKA and mobile-bearing TKA;the results meta-analysis showed no significant difference between the experimental and control groups(P=0.630).Two studies compared lateral retinacular release vs non-release;the meta-analysis showed a significant difference between the experimental and control groups(P=0.002);two other studies compared other factors.CONCLUSION Patellar resurfacing,mobile-bearing TKA,and fixed-bearing TKA do not reduce the incidence of AKP.Lateral retinacular release can reduce AKP;however,whether circumpatellar denervation can reduce AKP is controversial.展开更多
Parkinson’s disease(PD)is a common neurodegenerative disorder with no cure.Astragalus membranaceus is used in Chinese culture as a food supplement to boost immunity.The present study aimed to explore the neuroprotect...Parkinson’s disease(PD)is a common neurodegenerative disorder with no cure.Astragalus membranaceus is used in Chinese culture as a food supplement to boost immunity.The present study aimed to explore the neuroprotective effects of total flavonoids extracted from A.membranaceus(TFA)and their protective mechanisms.TFA offered neuroprotection against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)in the mouse model of Parkinsonism,by improving behavior performance in the gait analysis and pole test,and inhibiting the decline of tyrosine hydroxylase(TH)positive neurons and TH protein expression in substantia nigra of mice.TFA also prevented 1-methyl-4-phenylpyridinium(MPP+)induced neurotoxicity in SHSY5Y cells,by increasing GSH and GSH/GSSG ratio,and reducing reactive oxygen species.In addition,the neuroprotective effects of TFA were associated with its ability to restore MPTP/MPP+induced downregulation of SLC7A11 and glutathione peroxidase 4(GPX-4).In conclusion,we demonstrated that TFA exerted significant neuroprotection against MPTP/MPP+induced neurodegeneration by inhibiting ferroptosis through the regulation of SLC7A11/GPX-4 axis,suggesting the use of TFA as a possible food supplement in the prevention of PD.展开更多
The high-quality development of the construction industry fundamentally stems from the significant improvement of total factor productivity.Therefore,it is of crucial significance for promoting the development of the ...The high-quality development of the construction industry fundamentally stems from the significant improvement of total factor productivity.Therefore,it is of crucial significance for promoting the development of the construction industry to a higher level by scientifically and accurately measuring the total factor productivity of the construction industry and deeply analyzing the influencing factors behind it.Based on a comprehensive consideration of research methods and influencing factors,this paper systematically reviews the existing relevant literature on total factor productivity in the construction industry,aiming to reveal the current research development trend in this field and point out potential problems.This effort aims to provide a solid theoretical foundation and valuable reference for further in-depth research,and jointly promote the continuous progress and development of total factor productivity research in the construction industry.展开更多
Developing low-cost and green simultaneous desulfurization and denitrification technologies is of great significance for sulfur dioxide(SO_(2))and nitrogen oxide(NO_(x))emission control at low temperatures,especially ...Developing low-cost and green simultaneous desulfurization and denitrification technologies is of great significance for sulfur dioxide(SO_(2))and nitrogen oxide(NO_(x))emission control at low temperatures,especially for small and medium-sized coal-fired boilers and furnaces.Herein,phosphorus sludge,an industrial waste from the production process of yellow phosphorus,has been developed to simultaneously eliminate SO_(2)and NO_(x)from coal-fired flue gas.The key factors affecting the experimental results indicate that desulfurization and denitrification efficiency of over 95%can be achieved at a low temperature of 55℃.Further,the absorption mechanism was investigated by characterizing the solid and liquid phases of the phosphorus sludge during the absorption process.The efficient removal of SO_(2)is attributed to the abundance of iron(Fe^(3+))and manganese(Mn^(2+))in the absorbent.SO_(2)can be rapidly catalyzed and converted to SO_(4)^(2-)by them.The key to NOx removal is the oxidation of NO toward watersoluble high-valent nitrogen oxides by oxidizing reactive substances induced via yellow phosphorus,which are then absorbed by water and converted to NO_(3)^(-).Meanwhile,yellow phosphorus is oxidized to phosphoric acid(H_(3)PO_(4)).The spent absorption slurry can be reused through wet process phosphoric acid production,as it contains sulfuric acid(H_(2)SO_(4)),nitric acid(HNO_(3)),and H_(3)PO_(4).Accordingly,this is a technology with broad application prospects.展开更多
The aim of the present work is to assess the value of Detarium Senegalense by determining the content of total phenols, total flavonoids and total anthocyanins, and by evaluating the free radical scavenging activity o...The aim of the present work is to assess the value of Detarium Senegalense by determining the content of total phenols, total flavonoids and total anthocyanins, and by evaluating the free radical scavenging activity of Detarium Senegalense extracts. For this purpose, sequential extraction using solvents of increasing polarity was essential. The various extracts obtained underwent phytochemical and biochemical analyses. Phytochemical screening revealed the presence of flavonoids, alkaloids, tannins, polyphenols, anthocyanins and steroids/terpenes. Quantitative analysis of total polyphenols, total flavonoids and total anthocyanins yielded the following results: total flavonoids (0.803 ± 0029 mg EQ/100g P for acetone extract of roots and 0.871 ± 0.401 mg EQ/100g P for methanol extract of leaves);total polyphenols (23.298 ± 12.68 mg EAG/100g P for acetone extract of roots and 24.69 ± 0.49 401 mg EAG/100g P for methanol extract of leaves);total monomeric anthocyanins (44.697 ± 0.939 mg EC3G/100g P and 16.699 ± 0.193 mg EC3G/100g P respectively for acetone and methanol extracts of stem bark). DPPH free radical scavenging activity was 1.674 ± 0.023 mg/mL for the acetone extract and 0.934 ± 0.24 mg/mL for the methanol extract of roots. .展开更多
We investigate the anisotropic band structure and its evolution under tensile strains along different crystallographic directions in bulk black phosphorus(BP)using angle-resolved photoemission spectroscopy and density...We investigate the anisotropic band structure and its evolution under tensile strains along different crystallographic directions in bulk black phosphorus(BP)using angle-resolved photoemission spectroscopy and density functional theory.The results show that there are band crossings in the Z-L(armchair)direction.展开更多
Human activities lead to the accumulation of a large amount of nitrogen and phosphorus in sediments in rivers.Simultaneously,nitrogen and phosphorus can be affected by environment and re-enter the upper water body,cau...Human activities lead to the accumulation of a large amount of nitrogen and phosphorus in sediments in rivers.Simultaneously,nitrogen and phosphorus can be affected by environment and re-enter the upper water body,causing secondary pollution of the river water.In this study,laboratory simulation experiments were conducted initially to investigate the release of nitrogen and phosphorus from river sediments in Urumqi City and the surrounding areas in Xinjiang Uygur Autonomous Region of China and determine the factors that influence their release.The results of this study showed significant short-term differences in nitrogen and phosphorus release characteristics from sediments at different sampling points.The proposed secondary kinetics model(i.e.,pseudo-second-order kinetics model)better fitted the release process of sediment nitrogen and phosphorus.The release of nitrogen and phosphorus from sediments is a complex process driven by multiple factors,therefore,we tested the influence of three factors(pH,temperature,and disturbance intensity)on the release of nitrogen and phosphorus from sediments in this study.The most amount of nitrate nitrogen(NO_(3)^(–)-N)was released under neutral conditions,while the most significant release of ammonia nitrogen(NH_(4)^(+)-N)occurred under acidic and alkaline conditions.The release of nitrite nitrogen(NO_(2)^(-)-N)was less affected by pH.The dissolved total phosphorus(DTP)released significantly in the alkaline water environment,while the release of dissolved organic phosphorus(DOP)was more significant in acidic water.The release amount of soluble reactive phosphorus(SRP)increased with an increase in pH.The sediments released nitrogen and phosphorus at higher temperatures,particularly NH_(4)^(+)-N,NO_(3)^(–)-N,and SRP.The highest amount of DOP was released at 15.0℃.An increase in disturbance intensity exacerbated the release of nitrogen and phosphorus from sediments.NH_(4)^(+)-N,DTP,and SRP levels increased linearly with the intensity of disturbance,while NO_(3)^(–)-N and NO_(2)^(–)-N were more stable.This study provides valuable information for protecting and restoring the water environment in arid areas and has significant practical reference value.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.41571199,41030743,31870187)。
文摘To understand the relationship between planktonic diatoms and environmental variables in the lakes on the Songnen Plain,northeast(NE)China,we investigated water quality and planktonic diatoms from 71 sampling points in 27 lakes,based on which Canonical Correspondence Analysis(CCA)was conducted.The result show that planktonic diatoms displayed certain responses to environment gradients,and the total phosphorus(TP)explained the maximum variation of planktonic diatom species among the 15 environmental variables,suggesting that TP was the most important and significant environmental parameter affecting the distribution of diatom species.In addition,we established a diatom-total phosphorus transfer(DTPT)function,of which component 5 of the weighted averaging partial least squares regression(WAPLS)was chosen to and compared with a series of weighted average regression(WA)models and WA-PLS models.According to the jackknifing statistical test,the component 5 of WA-PLS models provided a lower root-mean-square error prediction(RMSEP=0.202)and a higher correlation coefficient between observation and prediction(R^2_Jack=0.759).After deletion of three outliers,the root-mean-square error prediction of the DTPT function was reduced(RMSEP=0.169)while the correlation coefficient between observation and prediction was increased(R^2_Jack=0.823).Therefore,this DTPT function performed better than other regional TP models in the world.However,it remains demanding for expanding the background dataset to improve the prediction ability of the model.
基金Supported by the National Science Foundation of China(61622301,61533002)Beijing Natural Science Foundation(4172005)Major National Science and Technology Project(2017ZX07104)
文摘The effluent total phosphorus(ETP) is an important parameter to evaluate the performance of wastewater treatment process(WWTP). In this study, a novel method, using a data-derived soft-sensor method, is proposed to obtain the reliable values of ETP online. First, a partial least square(PLS) method is introduced to select the related secondary variables of ETP based on the experimental data. Second, a radial basis function neural network(RBFNN) is developed to identify the relationship between the related secondary variables and ETP. This RBFNN easily optimizes the model parameters to improve the generalization ability of the soft-sensor. Finally, a monitoring system, based on the above PLS and RBFNN, named PLS-RBFNN-based soft-sensor system, is developed and tested in a real WWTP. Experimental results show that the proposed monitoring system can obtain the values of ETP online and own better predicting performance than some existing methods.
基金The research was supported by the National Basic Research Program(“973”Program)of China under contract No.2002CB412405the Key Science and Technology Plan of the Ministry of Education of China under contract No.[2000]156-00079the Joint Sino-German Project under contract No.03F0189A.
文摘Several methods for analysis of dissolved total phosphorus in seawater were reviewed. Discussions were focused on UVirradiation and persulphate oxidation methods which are the most popular dissolved organic phosphorus determinationmethods presently. The compounds used for the phosphorus recovery test were categorized into three groups accordingto their chemical structure. It was found that low power UV irradiation can decompose POC or PC bonds efficientlybut may be inefficient for POP bonds. Heating-bath in acid condition is useful for decomposing POP bonds. Usingthe continuous flow analysis system (Auto-analyzer II), UV digestion and heating-bath, series experiments were carriedout based on the above analysis. Eleven model compounds were employed for the phosphorus recovery test and thefactors influencing the decomposition efficiency of dissolved compounds containing phosphorus were clarified. Finally,the optimal design for determination of dissolved total phosphorus in seawater based on the routine continuous flowanalysis system was presented. For the organic mono-phosphate, the recovery is more than 90% and a recovery of33%~51% was obtained for inorganic or organic polyphosphates. Up to now, this is the highest decompositionefficiency for dissolved phosphorus based on the continuous flow analysis system.
基金This project was Supported by the National Science Foundation of China
文摘For some hundred surface sediment samples from five cores taken in two cruises near the Huanghe River Estuary, total phosphorus (TP (.inorganic phosphorus (IP (and organic phosphorus (OP)were determined.On the average, 527×10-6, 455×10~6 and 72×10-6 were found for TP,IP and OP for the surface sediments taken in the two cruises. The distribution of OP and IP was controlled by the sample particle size: OP content increased with the decreasing of the sample particle size, while the maximal value of IP was found in the silt fraction due to the existence of apatite in our samples. Vertical distributions reflected well the channel change of the Huanghe River. Results from the multiple regressions between the three forms of phosphorus and the percentages of different particle size agreed well with the analytical data.
基金supported by the K. C. Wong Education Foundation (GJTD-2018-08)the Natural Science Foundation of China (NSFC) (Grants 11804334, 51705192)+1 种基金the China Postdoctoral Science Foundation (2017M611325)the National Postdoctoral Program for Innovative Talents (BX201600064)
文摘Although abundant research on the anisotropy of van der Waals(vd W)materials has been published,we undertake an in-depth study of their optical properties as they have an important guiding role for light control in two-dimensional(2D)nanospace.As an example,we study the reflectance of few-layered black phosphorus(BP)in the total internal reflection(TIR)mode in detail.We demonstrate that its optical anisotropy can be changed on a large scale by varying the incident angles,polarization states,and the in-plane rotation angles of the BP samples.Theoretical analysis indicates that the phenomena observed are common to all the atom-thick biaxial crystals,so these conclusions can be widely applied to other anisotropic 2D materials.This research furthers the current understanding of the properties of BP more comprehensively,and provides guidance for developing new optoelectronic applications,especially when BP and other atom-thick biaxial crystals are integrated with TIR devices.
文摘The study was conducted to investigate the effect of Rhizobium inoculation and supplementation of phosphorus and potassium on growth and total leaf chlorophyll content to the three released bush bean varieties in northern Tanzania. To achieve this aim, the glasshouse experiment was conducted at Nelson Mandela African Institution of Science and Technology while field experiment were carried out at Tanzania Coffee Research Institute, in Kilimanjaro, Tanzania between April-July 2014. The experiment was laid out in factorial arrangement. Factor I comprised of three bush bean varieties. Factor II involved two inoculation treatments viz 1) inoculation with Rhizobium spp. and 2) without inoculation. Factor III included four fertilizer levels (0 Kg·ha-1 20 Kg K ha-1, 30 Kg P ha-1 and 20 kg·K + 30 Kg P ha-1). Both screen house and field experiments were replicated four times. Plant growth parameters (plant height (cm), number leaves per plant, stem girth (mm)) were measured at 2, 4 and 6 weaks after planting (WAP). The chlorophyll was extracted by using Dimethylsulphoxide (DMSO) and absorbance was determined at 645 and 663nm using UV/Visible spectrophotometer. Results showed that Rhizobium application significantly improved the number of leaves per plant, plant height, pant girth and total leaf chlorophyll content. Furthermore, compared with the zero treatment control, potassium fertilization significantly increased the number of leaves per plant, plant height, pant girth and total leaf chlorophyll content of the three varieties. In general, these parameters were significantly increased with phosphorus supplied at 30 kg/ha. The combination of these supplies at different levels resulted in significant interactions in some parameters and thus indicating need for these inputs in the study area.
基金Supported by Foundation for Young and Middle-aged Teachers in Fujian Province,China(JA15880)Undergraduate Training Program for Innovation and Entrepreneurship(201712709008)~~
文摘Total phosphorus is an important index in the monitoring of water quality, but the existing detection methods waste time and energy during the process of di- gestion. In this paper, the existing detection technology of total phosphorus and the digestion technology of organic phosphorus in the determination of total phosphorus were summarized firstly, of which photocatalytic degradation technology, as one of new technologies of organic phosphorus digestion, was introduced. Afterwards, tita- nium dioxide photocatalytic technology and its application were summarized, and its application prospects were expected.
文摘Effects of conservation methods of water samples on determination of total phosphorus were analyzed from aspects of methods of adding conserving agent, SS concentration, natural sedimentation time, conservation temperature and time. The results showed that SS concentration in water and natural sedimentation time had the greatest impact on the determination of total phosphorus, while the influence of methods of adding conserving agent, conservation temperature and time was relatively smaller. TP concentration in water samples conserved irregularly was higher than the standard value due to the existence of SS and microorganisms in water, and the deviation became larger with the increase of SS concentration in water. In addition, quality control measures and matters needing attention during the conservation process of water samples were put forward to improve the accuracy of TP concentration.
基金supported by the National Key R&D Program of China(2019YFD1002000,2016YFD0800602 and 2016YFD0501404)。
文摘Harnessing the rhizospheric microbiome,including phosphorus mineralizing bacteria(PMB),is a promising technique for maintaining sustainability and productivity in intensive agricultural systems.However,it is unclear as to which beneficial taxonomic group populations in the rhizosphere are potentially associated with the changes in soil microbiomes shifted by fertilization regimes.Herein,we analyzed the diversity and community structure of total bacteria and PMB in the rhizosphere of maize(Zea mays L.)grown in soils under 25 years of four fertilization regimes(compost,biocompost,chemical,or nonfertilized)via selective culture and Illumina sequencing of the 16S rRNA genes.Plant development explained more variations(29 and 13%,respectively)in the composition of total bacteria and PMB in the rhizosphere of maize than the different fertilization regimes.Among those genera enriched in the rhizosphere of maize,the relative abundances of Oceanobacillus,Bacillus,Achromobacter,Ensifer,Paracoccus,Ramlibacter,and Luteimonas were positively correlated with those in the bulk soil.The relative abundance of Paracoccus was significantly higher in soils fertilized by compost or biocompost than the other soils.Similar results were also observed for PMB affiliated with Ensifer,Bacillus,and Streptomyces.Although plant development was the major factor in shaping the rhizospheric microbiome of maize,fertilization regimes might have modified beneficial rhizospheric microbial taxa such as Bacillus and Ensifer.
基金Supported by Sichuan Province Science and Technology Planning Project(Key R&D Project)(2017SZ0177)Scientific Research Project of Education Department of Sichuan Province(18ZB0020)+1 种基金Major Cultivation Project of Chengdu Textile College(2015fzlka01)High-quality Restoration of Damaged Water Body(500245H20002).
文摘Based on previous studies,the effects of the type,content,particle size and state of sediment on the determination of total phosphorus in water are analyzed.The results show that the type of sediment has a certain influence on the determination result of total phosphorus,and the influence cannot be ignored.The degree of influence depends on the specific type.Sediment content is negatively correlated with the determination result of total phosphorus in water.That is,the higher the sediment content is,the lower the determination result is.The particle size of sediment is positively correlated with the determination result of total phosphorus in water.That is,the larger the particle size of sediment is,the higher the determination result is.Among the static,semi-suspended and completely suspended states,the sediment in the static state has the least impact on the determination of total phosphorus,and it has the greatest impact on the determination of total phosphorus when it is fully suspended.Therefore,in the analysis and testing process of total phosphorus,attention should be paid to the impact of sediment to improve the authenticity of the test results.
文摘BACKGROUND Total hip arthroplasty is as an effective intervention to relieve pain and improve hip function.Approaches of the hip have been exhaustively explored about pros and cons.The efficacy and the complications of hip approaches remains inconclusive.This study conducted an umbrella review to systematically appraise previous meta-analysis(MAs)including conventional posterior approach(PA),and minimally invasive surgeries as the lateral approach(LA),direct anterior approach(DAA),2-incisions method,mini-lateral approach and the newest technique direct superior approach(DSA)or supercapsular percutaneouslyassisted total hip(SuperPath).AIM To compare the efficacy and complications of hip approaches that have been published in all MAs and randomized controlled trials(RCTs).METHODS MAs were identified from MEDLINE and Scopus from inception until 2023.RCTs were then updated from the latest MA to September 2023.This study included studies which compared hip approaches and reported at least one outcome such as Harris Hip Score(HHS),dislocation,intra-operative fracture,wound compliData were independently selected,extracted and assessed by two reviewers.Network MA and cluster rank and surface under the cumulative ranking curve(SUCRA)were estimated for treatment efficacy and safety.RESULTS Finally,twenty-eight MAs(40 RCTs),and 13 RCTs were retrieved.In total 47 RCTs were included for reanalysis.The results of corrected covered area showed high degree(13.80%).Among 47 RCTs,most of the studies were low risk of bias in part of random process and outcome reporting,while other domains were medium to high risk of bias.DAA significantly provided higher HHS at three months than PA[pooled unstandardized mean difference(USMD):3.49,95%confidence interval(CI):0.98,6.00 with SUCRA:85.9],followed by DSA/SuperPath(USMD:1.57,95%CI:-1.55,4.69 with SUCRA:57.6).All approaches had indifferent dislocation and intraoperative fracture rates.SUCRA comparing early functional outcome and composite complications(dislocation,intra-operative fracture,wound complication,and nerve injury)found DAA was the best approach followed by DSA/SuperPath.CONCLUSION DSA/SuperPath had better earlier functional outcome than PA,but still could not overcome the result of DAA.This technique might be the other preferred option with acceptable complications.
基金supported by National Natural Science Foundation of China(No.51902250).
文摘The crossmodal interaction of different senses,which is an important basis for learning and memory in the human brain,is highly desired to be mimicked at the device level for developing neuromorphic crossmodal perception,but related researches are scarce.Here,we demonstrate an optoelectronic synapse for vision-olfactory crossmodal perception based on MXene/violet phosphorus(VP)van der Waals heterojunctions.Benefiting from the efficient separation and transport of photogenerated carriers facilitated by conductive MXene,the photoelectric responsivity of VP is dramatically enhanced by 7 orders of magnitude,reaching up to 7.7 A W^(−1).Excited by ultraviolet light,multiple synaptic functions,including excitatory postsynaptic currents,pairedpulse facilitation,short/long-term plasticity and“learning-experience”behavior,were demonstrated with a low power consumption.Furthermore,the proposed optoelectronic synapse exhibits distinct synaptic behaviors in different gas environments,enabling it to simulate the interaction of visual and olfactory information for crossmodal perception.This work demonstrates the great potential of VP in optoelectronics and provides a promising platform for applications such as virtual reality and neurorobotics.
基金Supported by The National Institutes of Health,No.R01HL147155 and No.R01AG060920.
文摘BACKGROUND There is concern regarding potential long-term cardiotoxicity with systemic distribution of metals in total joint arthroplasty(TJA)patients.AIM To determine the association of commonly used implant metals with echocardiographic measures in TJA patients.METHODS The study comprised 110 TJA patients who had a recent history of high chromium,cobalt or titanium concentrations.Patients underwent two-dimensional,three-dimensional,Doppler and speckle-strain transthoracic echocardiography and a blood draw to measure metal concentrations.Age and sex-adjusted linear and logistic regression models were used to examine the association of metal concentrations(exposure)with echocardiographic measures(outcome).RESULTS Higher cobalt concentrations were associated with increased left ventricular end-diastolic volume(estimate 5.09;95%CI:0.02-10.17)as well as left atrial and right ventricular dilation,particularly in men but no changes in cardiac function.Higher titanium concentrations were associated with a reduction in left ventricle global longitudinal strain(estimate 0.38;95%CI:0.70 to 0.06)and cardiac index(estimate 0.08;95%CI,-0.15 to-0.01).CONCLUSION Elevated cobalt and titanium concentrations may be associated with structural and functional cardiac changes in some patients.Longitudinal studies are warranted to better understand the systemic effects of metals in TJA patients.
基金Supported by the Capital Fund Project for Clinical Diagnosis and Treatment Technology Research and Translational Application,No.Z201100005520091and Beijing Traditional Chinese Medicine Science and Technology Development Fund Project,No.JJ-2020-67.
文摘BACKGROUND Total knee arthroplasty(TKA)is a mature procedure recommended for correcting knee osteoarthritis deformity,relieving pain,and restoring normal biomechanics.Although TKA is a successful and cost-effective procedure,patient dissatisfaction is as high as 50%.Knee pain after TKA is a significant cause of patient dissatisfaction;the most common location for residual pain is the anterior region.Between 4%and 40%of patients have anterior knee pain(AKP).AIM To investigate the effect of various TKA procedures on postoperative AKP.METHODS We searched PubMed,EMBASE,and Cochrane from January 2000 to September 2022.Randomized controlled trials with one intervention in the experimental group and no corresponding intervention(or other interventions)in the control group were collected.Two researchers independently read the title and abstract of the studies,preliminarily screened the articles,and read the full text in detail according to the selection criteria.Conflicts were resolved by consultation with a third researcher.And relevant data from the included studies were extracted and analyzed using Review Manager 5.4 software.RESULTS There were 25 randomized controlled trials;13 were comparative studies with or without patellar resurfacing.The meta-analysis showed no significant difference between the experimental and control groups(P=0.61).Six studies were comparative studies of circumpatellar denervation vs non-denervation,divided into three subgroups for meta-analysis.The two-subgroup meta-analysis showed no significant difference between the experimental and the control groups(P=0.31,P=0.50).One subgroup meta-analysis showed a significant difference between the experimental and control groups(P=0.001).Two studies compared fixed-bearing TKA and mobile-bearing TKA;the results meta-analysis showed no significant difference between the experimental and control groups(P=0.630).Two studies compared lateral retinacular release vs non-release;the meta-analysis showed a significant difference between the experimental and control groups(P=0.002);two other studies compared other factors.CONCLUSION Patellar resurfacing,mobile-bearing TKA,and fixed-bearing TKA do not reduce the incidence of AKP.Lateral retinacular release can reduce AKP;however,whether circumpatellar denervation can reduce AKP is controversial.
文摘Parkinson’s disease(PD)is a common neurodegenerative disorder with no cure.Astragalus membranaceus is used in Chinese culture as a food supplement to boost immunity.The present study aimed to explore the neuroprotective effects of total flavonoids extracted from A.membranaceus(TFA)and their protective mechanisms.TFA offered neuroprotection against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)in the mouse model of Parkinsonism,by improving behavior performance in the gait analysis and pole test,and inhibiting the decline of tyrosine hydroxylase(TH)positive neurons and TH protein expression in substantia nigra of mice.TFA also prevented 1-methyl-4-phenylpyridinium(MPP+)induced neurotoxicity in SHSY5Y cells,by increasing GSH and GSH/GSSG ratio,and reducing reactive oxygen species.In addition,the neuroprotective effects of TFA were associated with its ability to restore MPTP/MPP+induced downregulation of SLC7A11 and glutathione peroxidase 4(GPX-4).In conclusion,we demonstrated that TFA exerted significant neuroprotection against MPTP/MPP+induced neurodegeneration by inhibiting ferroptosis through the regulation of SLC7A11/GPX-4 axis,suggesting the use of TFA as a possible food supplement in the prevention of PD.
基金Supported by School-level Natural Science Project of Jiangxi University of Technology(232ZRYB02).
文摘The high-quality development of the construction industry fundamentally stems from the significant improvement of total factor productivity.Therefore,it is of crucial significance for promoting the development of the construction industry to a higher level by scientifically and accurately measuring the total factor productivity of the construction industry and deeply analyzing the influencing factors behind it.Based on a comprehensive consideration of research methods and influencing factors,this paper systematically reviews the existing relevant literature on total factor productivity in the construction industry,aiming to reveal the current research development trend in this field and point out potential problems.This effort aims to provide a solid theoretical foundation and valuable reference for further in-depth research,and jointly promote the continuous progress and development of total factor productivity research in the construction industry.
基金The National Natural Science Foundation of China (22068019)Yunnan Major Scientific and Technological Projects (202202AG050001)
文摘Developing low-cost and green simultaneous desulfurization and denitrification technologies is of great significance for sulfur dioxide(SO_(2))and nitrogen oxide(NO_(x))emission control at low temperatures,especially for small and medium-sized coal-fired boilers and furnaces.Herein,phosphorus sludge,an industrial waste from the production process of yellow phosphorus,has been developed to simultaneously eliminate SO_(2)and NO_(x)from coal-fired flue gas.The key factors affecting the experimental results indicate that desulfurization and denitrification efficiency of over 95%can be achieved at a low temperature of 55℃.Further,the absorption mechanism was investigated by characterizing the solid and liquid phases of the phosphorus sludge during the absorption process.The efficient removal of SO_(2)is attributed to the abundance of iron(Fe^(3+))and manganese(Mn^(2+))in the absorbent.SO_(2)can be rapidly catalyzed and converted to SO_(4)^(2-)by them.The key to NOx removal is the oxidation of NO toward watersoluble high-valent nitrogen oxides by oxidizing reactive substances induced via yellow phosphorus,which are then absorbed by water and converted to NO_(3)^(-).Meanwhile,yellow phosphorus is oxidized to phosphoric acid(H_(3)PO_(4)).The spent absorption slurry can be reused through wet process phosphoric acid production,as it contains sulfuric acid(H_(2)SO_(4)),nitric acid(HNO_(3)),and H_(3)PO_(4).Accordingly,this is a technology with broad application prospects.
文摘The aim of the present work is to assess the value of Detarium Senegalense by determining the content of total phenols, total flavonoids and total anthocyanins, and by evaluating the free radical scavenging activity of Detarium Senegalense extracts. For this purpose, sequential extraction using solvents of increasing polarity was essential. The various extracts obtained underwent phytochemical and biochemical analyses. Phytochemical screening revealed the presence of flavonoids, alkaloids, tannins, polyphenols, anthocyanins and steroids/terpenes. Quantitative analysis of total polyphenols, total flavonoids and total anthocyanins yielded the following results: total flavonoids (0.803 ± 0029 mg EQ/100g P for acetone extract of roots and 0.871 ± 0.401 mg EQ/100g P for methanol extract of leaves);total polyphenols (23.298 ± 12.68 mg EAG/100g P for acetone extract of roots and 24.69 ± 0.49 401 mg EAG/100g P for methanol extract of leaves);total monomeric anthocyanins (44.697 ± 0.939 mg EC3G/100g P and 16.699 ± 0.193 mg EC3G/100g P respectively for acetone and methanol extracts of stem bark). DPPH free radical scavenging activity was 1.674 ± 0.023 mg/mL for the acetone extract and 0.934 ± 0.24 mg/mL for the methanol extract of roots. .
基金supported by the National Natural Science Foundation of China(Grant Nos.12104216,12241403,and 61974061)the National Key R&D Program of China(Grant No.2021YFB3601600)the Natural Science Foundation of Jiangsu Province of China(Grant No.BK20140054)。
文摘We investigate the anisotropic band structure and its evolution under tensile strains along different crystallographic directions in bulk black phosphorus(BP)using angle-resolved photoemission spectroscopy and density functional theory.The results show that there are band crossings in the Z-L(armchair)direction.
基金the Xinjiang Science and Technology Support Project Plan(2022E02026)the Xinjiang Agricultural University Graduate Research and Innovation Programme(XJAUGRI2023049).
文摘Human activities lead to the accumulation of a large amount of nitrogen and phosphorus in sediments in rivers.Simultaneously,nitrogen and phosphorus can be affected by environment and re-enter the upper water body,causing secondary pollution of the river water.In this study,laboratory simulation experiments were conducted initially to investigate the release of nitrogen and phosphorus from river sediments in Urumqi City and the surrounding areas in Xinjiang Uygur Autonomous Region of China and determine the factors that influence their release.The results of this study showed significant short-term differences in nitrogen and phosphorus release characteristics from sediments at different sampling points.The proposed secondary kinetics model(i.e.,pseudo-second-order kinetics model)better fitted the release process of sediment nitrogen and phosphorus.The release of nitrogen and phosphorus from sediments is a complex process driven by multiple factors,therefore,we tested the influence of three factors(pH,temperature,and disturbance intensity)on the release of nitrogen and phosphorus from sediments in this study.The most amount of nitrate nitrogen(NO_(3)^(–)-N)was released under neutral conditions,while the most significant release of ammonia nitrogen(NH_(4)^(+)-N)occurred under acidic and alkaline conditions.The release of nitrite nitrogen(NO_(2)^(-)-N)was less affected by pH.The dissolved total phosphorus(DTP)released significantly in the alkaline water environment,while the release of dissolved organic phosphorus(DOP)was more significant in acidic water.The release amount of soluble reactive phosphorus(SRP)increased with an increase in pH.The sediments released nitrogen and phosphorus at higher temperatures,particularly NH_(4)^(+)-N,NO_(3)^(–)-N,and SRP.The highest amount of DOP was released at 15.0℃.An increase in disturbance intensity exacerbated the release of nitrogen and phosphorus from sediments.NH_(4)^(+)-N,DTP,and SRP levels increased linearly with the intensity of disturbance,while NO_(3)^(–)-N and NO_(2)^(–)-N were more stable.This study provides valuable information for protecting and restoring the water environment in arid areas and has significant practical reference value.