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Grain yield and N uptake of maize in response to increased plant density under reduced water and nitrogen supply conditions 被引量:1
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作者 Jingui Wei Qiang Chai +5 位作者 Wen Yin Hong Fan Yao Guo Falong Hu Zhilong Fan QimingWang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期122-140,共19页
The development of modern agriculture requires the reduction of water and chemical N fertilizer inputs.Increasing the planting density can maintain higher yields,but also consumes more of these restrictive resources.H... The development of modern agriculture requires the reduction of water and chemical N fertilizer inputs.Increasing the planting density can maintain higher yields,but also consumes more of these restrictive resources.However,whether an increased maize density can compensate for the negative effects of reduced water and N supply on grain yield and N uptake in the arid irrigated areas remains unknown.This study is part of a long-term positioning trial that started in 2016.A split-split plot field experiment of maize was implemented in the arid irrigated area of northwestern China in 2020 to 2021.The treatments included two irrigation levels:local conventional irrigation reduced by 20%(W1,3,240 m^(3)ha^(-1))and local conventional irrigation(W2,4,050 m^(3)ha^(-1));two N application rates:local conventional N reduced by 25%(N1,270 kg ha^(-1))and local conventional N(360 kg ha^(-1));and three planting densities:local conventional density(D1,75,000 plants ha^(-1)),density increased by 30%(D2,97,500 plants ha-1),and density increased by 60%(D3,120,000 plants ha^(-1)).Our results showed that the grain yield and aboveground N accumulation of maize were lower under the reduced water and N inputs,but increasing the maize density by 30% can compensate for the reductions of grain yield and aboveground N accumulation caused by the reduced water and N supply.When water was reduced while the N application rate remained unchanged,increasing the planting density by 30% enhanced grain yield by 13.9% and aboveground N accumulation by 15.3%.Under reduced water and N inputs,increasing the maize density by 30% enhanced N uptake efficiency and N partial factor productivity,and it also compensated for the N harvest index and N metabolic related enzyme activities.Compared with W2N2D1,the N uptake efficiency and N partial factor productivity increased by 28.6 and 17.6%under W1N1D2.W1N2D2 had 8.4% higher N uptake efficiency and 13.9% higher N partial factor productivity than W2N2D1.W1N2D2 improved urease activity and nitrate reductase activity by 5.4% at the R2(blister)stage and 19.6% at the V6(6th leaf)stage,and increased net income and the benefit:cost ratio by 22.1 and 16.7%,respectively.W1N1D2 and W1N2D2 reduced the nitrate nitrogen and ammoniacal nitrogen contents at the R6 stage in the 40-100 cm soil layer,compared with W2N2D1.In summary,increasing the planting density by 30% can compensate for the loss of grain yield and aboveground N accumulation under reduced water and N inputs.Meanwhile,increasing the maize density by 30% improved grain yield and aboveground N accumulation when water was reduced by 20% while the N application rate remained constant in arid irrigation areas. 展开更多
关键词 water and N reduction plant density MAIZE grain yield N uptake compensation effect
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Structural properties of residual carbon in coal gasification fine slag and their influence on flotation separation and resource utilization:A review 被引量:3
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作者 Rui Han Anning Zhou +4 位作者 Ningning Zhang Kaiqiang Guo Mengyan Cheng Heng Chen Cuicui Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期217-230,共14页
Coal gasification fine slag(FS)is a typical solid waste generated in coal gasification.Its current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological hazards.Separation recovery a... Coal gasification fine slag(FS)is a typical solid waste generated in coal gasification.Its current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological hazards.Separation recovery and the high-value utilization of residual carbon(RC)in FS are the keys to realizing the win-win situation of the coal chemical industry in terms of economic and environmental benefits.The structural properties,such as pore,surface functional group,and microcrystalline structures,of RC in FS(FS-RC)not only affect the flotation recovery efficiency of FS-RC but also form the basis for the high-value utilization of FS-RC.In this paper,the characteristics of FS-RC in terms of pore structure,surface functional groups,and microcrystalline structure are sorted out in accordance with gasification type and FS particle size.The reasons for the formation of the special structural properties of FS-RC are analyzed,and their influence on the flotation separation and high-value utilization of FS-RC is summarized.Separation methods based on the pore structural characterist-ics of FS-RC,such as ultrasonic pretreatment-pore-blocking flotation and pore breaking-flocculation flotation,are proposed to be the key development technologies for improving FS-RC recovery in the future.The design of low-cost,low-dose collectors containing polar bonds based on the surface and microcrystalline structures of FS-RC is proposed to be an important breakthrough point for strengthening the flotation efficiency of FS-RC in the future.The high-value utilization of FS should be based on the physicochemical structural proper-ties of FS-RC and should focus on the environmental impact of hazardous elements and the recyclability of chemical waste liquid to es-tablish an environmentally friendly utilization method.This review is of great theoretical importance for the comprehensive understand-ing of the unique structural properties of FS-RC,the breakthrough of the technological bottleneck in the efficient flotation separation of FS,and the expansion of the field of the high value-added utilization of FS-RC. 展开更多
关键词 coal gasification fine slag residual carbon pore structure surface functional groups microcrystalline structure flotation sep-aration resource utilization
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Potassium nutrition of maize:Uptake,transport,utilization,and role in stress tolerance 被引量:1
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作者 Meiling Zhang Yingying Hu +3 位作者 Wu Han Jian Chen Jinsheng Lai Yi Wang 《The Crop Journal》 SCIE CSCD 2023年第4期1048-1058,共11页
Potassium(K) is an essential macronutrient for plant growth and development and influences yield and quality of agricultural crops.Maize(Zea mays) is one of the most widely distributed crops worldwide.In China,althoug... Potassium(K) is an essential macronutrient for plant growth and development and influences yield and quality of agricultural crops.Maize(Zea mays) is one of the most widely distributed crops worldwide.In China,although maize consumes a large amount of K fertilizer,the K uptake/utilization efficiency(KUE)of maize cultivars is relatively low.Elucidation of KUE mechanisms and development of maize cultivars with higher KUE are needed.Maize KUE is determined by K+uptake,transport,and remobilization,which depend on a variety of K+channels and transporters.We review basic information about K+channels and transporters in maize,their functions and regulation,and the roles of K+in nitrogen transport,sugar transport,and salt tolerance.We discuss challenges and prospects for maize KUE improvement. 展开更多
关键词 MAIZE POTASSIUM CHANNEL TRANSPORTER K uptake/utilization efficiency
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COVID-19 Vaccination Uptake and Associated Factors in Selected Communities in Two Southwestern States in Nigeria
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作者 Oluseye Ayodele Ajayi Olabanjo Okunlola Ogunsola +4 位作者 Ajibola Idowu Oluwaseun Kikelomo Ajayi Kucheli Wudiri Rita Asoka-Ikechukwu Prosper Okonkwo 《Advances in Infectious Diseases》 CAS 2024年第1期260-278,共19页
Introduction: COVID-19 vaccine uptake and acceptance have been a major global concern due to the prevalent misinformation and disinformation that has characterized the vaccine rollout worldwide. This study aimed to as... Introduction: COVID-19 vaccine uptake and acceptance have been a major global concern due to the prevalent misinformation and disinformation that has characterized the vaccine rollout worldwide. This study aimed to assess COVID-19 vaccine uptake and acceptance, and associated factors among selected community members in two states in southwestern Nigeria. Method: We conducted a cross-sectional study using a multistage sampling technique. Fifty catchment settlements of 10 health facilities in each of Oyo and Ogun States targeted for a COVID-19 infection prevention and control intervention were randomly selected. Four households were targeted per settlement. All households that refused access were replaced, to ensure a minimum of four households randomly selected per settlement. The primary household decision-maker was interviewed in each household. Information elicited included respondents’ sociodemographic characteristics, health history, knowledge, risk and benefit perception about the COVID-19 vaccine, vaccine uptake, and willingness to be vaccinated. The study was conducted from July–August 2021. Data were analyzed using SPSS IBM version 23. Result: Four hundred household decision-makers were surveyed in Oyo and Ogun states, after replacement. The mean age of the respondents was 43.0 ± 11.0 years. The majority, 346 (86.5%) had heard about COVID-19 vaccination, but only 47 (13.6%) had received a COVID-19 vaccination. Of the 299 respondents who reported not receiving a COVID-19 vaccination, 166 (55.5%) were willing to be vaccinated. In  univariate analysis, respondents who were female had tertiary education, perceived that COVID-19 vaccines are free and accessible, perceived that COVID-19 vaccines have minimal side effects, and perceived higher benefits of COVID-19 vaccination had higher odds of being vaccinated. In contrast, younger respondents, respondents with higher knowledge scores on COVID-19 preventive measures, and with chronic illness had lower likelihoods of being vaccinated. In multivariate analysis, only the respondent’s age, perception score on COVID-19 vaccine benefits, knowledge score on IPC measures, and positive response on accessibility and safety were significant after adjusting for other factors. Conclusion: COVID-19 vaccine uptake rate as well as willingness to receive vaccination were low in the study setting. There is an urgent need for policymakers to embark on well-designed campaigns to address barriers to COVID-19 vaccination to increase vaccine uptake. 展开更多
关键词 COVID-19 VACCINATION VACCINE Vaccine uptake
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Methods,Mechanisms,and Application Prospects for Enhancing Extracellular Vesicle Uptake
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作者 Ying-peng XU Tao JIANG +1 位作者 Xiao-fan YANG Zhen-bing CHEN 《Current Medical Science》 SCIE CAS 2024年第2期247-260,共14页
Extracellular vesicles(EVs)are considered to be a new generation of bioinspired nanoscale drug delivery systems due to their low immunogenicity,natural functionality,and excellent biocompatibility.However,limitations ... Extracellular vesicles(EVs)are considered to be a new generation of bioinspired nanoscale drug delivery systems due to their low immunogenicity,natural functionality,and excellent biocompatibility.However,limitations such as low uptake efficiency,insufficient production,and inhomogeneous performance undermine their potential.To address these issues,numerous researchers have put forward various methods and applications for enhancing EV uptake in recent decades.In this review,we introduce various methods for the cellular uptake of EVs and summarize recent advances on the methods and mechanisms for enhancing EV uptake.In addition,we provide further understanding regarding enhancing EV uptake and put forward prospects and challenges for the development of EV-based therapy in the future. 展开更多
关键词 extracellular vesicles EXOSOMES extracellular vesicle uptake extracellular vesiclebased therapy
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Socio-Demographic and Economic Factors Associated with Uptake of COVID-19 Vaccine among Pregnant Women at Pumwani Maternity Hospital in Nairobi County, Kenya
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作者 Nyawela S. Nyibil Gideon Kikuvi Isabel Kazanga Chiumia 《Open Journal of Epidemiology》 2024年第2期221-237,共17页
Introduction: Pregnant women are a highly vulnerable population for COVID-19 with increased risk of hospitalization, intensive-care unit admission, invasive ventilation support, and mortality. Objective: This study de... Introduction: Pregnant women are a highly vulnerable population for COVID-19 with increased risk of hospitalization, intensive-care unit admission, invasive ventilation support, and mortality. Objective: This study determined the socio-demographic and economic factors associated with the uptake of COVID-19 vaccine among pregnant women utilizing antenatal care services in Pumwani Maternity Hospital, Nairobi County-Kenya. Methods: The study was carried out from 15 June to 23 July 2023. Systematic sampling was used to select 302 women from whom data was collected through face-to-face interviews using a pre-tested semi-structured questionnaire. Data was analyzed using SPSS software in which bivariate and multivariate logistic regression analyses were done at a significance level of p Results: A total of 302 pregnant women participated in the study. Of these, 105 (34.8%) were aged between twenty-six (26) and thirty (30) years. The mean age of the women was 28.60 ± (SD = 5.297). The uptake of the COVID-19 vaccine was 41.1%. The common side effects reported to be associated with the vaccines were fever, headache, joint pain, vomiting and skin rash. Uptake of the COVID-19 vaccine was significantly associated with being married (AOR = 3.65, 95% CI: 0.62 - 1.80, p = 0.001), having a secondary level of education (AOR = 3.78, 95% CI: 0.99 - 2.88, p = 0.001) and being employed (COR = 2.66, 95% CI: 1.31 - 3.06, p = 0.001). Conclusion: COVID-19 vaccination uptake remains low among pregnant women in seeking ANC in Nairobi. The individual factors associated with the uptake of COVID-19 vaccine among pregnant Women at Pumwani maternity hospital in Nairobi County were being married, having secondary level of education and being employed. Integration of the COVID-19 vaccine with other routine vaccinations as per the national immunization program in Kenya and the enhancement of education regarding the safety and efficacy of the COVID-19 vaccine in pregnancy and breastfeeding and economic empowerment of women are recommended. 展开更多
关键词 COVID-19 Vaccine uptake Associated Factors Pregnant Women
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Combined application of organic fertilizer and chemical fertilizer alleviates the kernel position effect in summer maize by promoting post-silking nitrogen uptake and dry matter accumulation
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作者 Lichao Zhai Lihua Zhang +7 位作者 Yongzeng Cui Lifang Zhai Mengjing Zheng Yanrong Yao Jingting Zhang Wanbin Hou Liyong Wu Xiuling Jia 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1179-1194,共16页
Adjusting agronomic measures to alleviate the kernel position effect in maize is important for ensuring high yields.In order to clarify whether the combined application of organic fertilizer and chemical fertilizer(CA... Adjusting agronomic measures to alleviate the kernel position effect in maize is important for ensuring high yields.In order to clarify whether the combined application of organic fertilizer and chemical fertilizer(CAOFCF)can alleviate the kernel position effect of summer maize,field experiments were conducted during the 2019 and 2020 growing seasons,and five treatments were assessed:CF,100%chemical fertilizer;OFCF1,15%organic fertilizer+85%chemical fertilizer;OFCF2,30%organic fertilizer+70%chemical fertilizer;OFCF3,45%organic fertilizer+55%chemical fertilizer;and OFCF4,60%organic fertilizer+40%chemical fertilizer.Compared with the CF treatment,the OFCF1 and OFCF2 treatments significantly alleviated the kernel position effect by increasing the weight ratio of inferior kernels to superior kernels and reducing the weight gap between the superior and inferior kernels.These effects were largely due to the improved filling and starch accumulation of inferior kernels.However,there were no obvious differences in the kernel position effect among plants treated with CF,OFCF3,or OFCF4 in most cases.Leaf area indexes,post-silking photosynthetic rates,and net assimilation rates were higher in plants treated with OFCF1 or OFCF2 than in those treated with CF,reflecting an enhanced photosynthetic capacity and improved postsilking dry matter accumulation(DMA)in the plants treated with OFCF1 or OFCF2.Compared with the CF treatment,the OFCF1 and OFCF2 treatments increased post-silking N uptake by 66.3 and 75.5%,respectively,which was the major factor driving post-silking photosynthetic capacity and DMA.Moreover,the increases in root DMA and zeatin riboside content observed following the OFCF1 and OFCF2 treatments resulted in reduced root senescence,which is associated with an increased post-silking N uptake.Analyses showed that post-silking N uptake,DMA,and grain yield in summer maize were negatively correlated with the kernel position effect.In conclusion,the combined application of 15-30%organic fertilizer and 70-85%chemical fertilizer alleviated the kernel position effect in summer maize by improving post-silking N uptake and DMA.These results provide new insights into how CAOFCF can be used to improve maize productivity. 展开更多
关键词 chemical fertilizer dry mater accumulation kernel position effect N uptake organic fertilizer
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OsNPF3.1,a nitrate,abscisic acid and gibberellin transporter gene,is essential for rice tillering and nitrogen utilization efficiency
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作者 Junnan Hang Bowen Wu +3 位作者 Diyang Qiu Guo Yang Zhongming Fang Mingyong Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1087-1104,共18页
Low-affinity nitrate transporter genes have been identified in subfamilies 4-8 of the rice nitrate transporter 1(NRT1)/peptide transporter family(NPF),but the OsNPF3 subfamily responsible for nitrate and phytohormone ... Low-affinity nitrate transporter genes have been identified in subfamilies 4-8 of the rice nitrate transporter 1(NRT1)/peptide transporter family(NPF),but the OsNPF3 subfamily responsible for nitrate and phytohormone transport and rice growth and development remains unknown.In this study,we described OsNPF3.1 as an essential nitrate and phytohormone transporter gene for rice tillering and nitrogen utilization efficiency(NUtE).OsNPF3.1 possesses four major haplotypes of its promoter sequence in 517 cultivars,and its expression is positively associated with tiller number.Its expression was higher in the basal part,culm,and leaf blade than in other parts of the plant,and was strongly induced by nitrate,abscisic acid(ABA)and gibberellin 3(GA_3)in the root and shoot of rice.Electrophysiological experiments demonstrated that OsNPF3.1 is a pH-dependent low-affinity nitrate transporter,with rice protoplast uptake assays showing it to be an ABA and GA_3 transporter.OsNPF3.1 overexpression significantly promoted ABA accumulation in the roots and GA accumulation in the basal part of the plant which inhibited axillary bud outgrowth and rice tillering,especially at high nitrate concentrations.The NUtE of OsNPF3.1-overexpressing plants was enhanced under low and medium nitrate concentrations,whereas the NUtE of OsNPF3.1 clustered regularly interspaced short palindromic repeats(CRISPR)plants was increased under high nitrate concentrations.The results indicate that OsNPF3.1 transports nitrate and phytohormones in different rice tissues under different nitrate concentrations.The altered OsNPF3.1 expression improves NUtE in the OsNPF3.1-overexpressing and CRISPR lines at low and high nitrate concentrations,respectively. 展开更多
关键词 rice tillering grain yield PHYTOHORMONE NITRATE transporter nitrogen utilization efficiency
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Comprehensive reutilization of herbal waste:Coproduction of magnolol,honokiol,and β-amyrin from Magnolia officinalis residue
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作者 Lukun Xiao Anyi Zhao +12 位作者 Jie Qiu An Liu Sha Chen Jinzhu Jiang Jun Zhang Cong Guo Jipeng Di Jintang Cheng Chang Chen Kangxin Hou Aiping Zhang Yan Liu Caixia Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第2期403-412,共10页
Herbal extraction residues(HERs)cause serious environmental pollution and resource waste.In this study,a novel green route was designed for the comprehensive reutilization of all components in HERs,taking Magnolia off... Herbal extraction residues(HERs)cause serious environmental pollution and resource waste.In this study,a novel green route was designed for the comprehensive reutilization of all components in HERs,taking Magnolia officinalis residues(MOR)as an example.The reluctant structure of MOR was first destroyed by alkali pretreatment to release the functional ingredients(magnolol and honokiol)originally remaining in MOR and to make MOR more accessible for hydrolysis.A metal–organic frame material MIL-101(Cr)with a maximum absorption capacity of 255.64 mg g^(-1)was synthesized to absorb the released honokiol and magnolol from the pretreated MOR solutions,and 40 g L^(-1)reducing sugars were obtained with 81.8%enzymatic hydrolysis rate at 10%MOR solid loading.Finally,382 mg L-1β-amyrin was produced from MOR hydrolysates by an engineered yeast strain.In total,1 kg honokiol,8 kg magnolol,and 7.64 kg β-amyrin could produce from 1 ton MOR by this cleaner process with a total economic output of 170,700 RMB. 展开更多
关键词 Magnolia officinalis residues(MOR) Comprehensive utilization Metal-organic frame material BIOSYNTHESIS
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Analysis and Prospect of Waste Heat Utilization from Blast Furnace Slag Flushing
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作者 Shenqin Zhang Junyi Qing 《Frontiers of Metallurgical Industry》 2024年第2期15-20,共6页
Estimating the residual heat of blast furnace slag flushing in China,classifying and introducing the current proposed methods of slag flushing waste heat utilization,and listing existing cases.In order to better save ... Estimating the residual heat of blast furnace slag flushing in China,classifying and introducing the current proposed methods of slag flushing waste heat utilization,and listing existing cases.In order to better save energy and water in the slag flushing process of blast furnaces,an ideal comprehensive cascade utilization system scheme for annual recovery of waste heat is proposed.Based on the measured waste heat data of a steel plant,design calculations are carried out to further analyze the economic feasibility of the new scheme and provide reference for its promotion and application. 展开更多
关键词 blast furnace slag flushing waste heat utilization comprehensive cascade utilization energy saving and water-saving
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Optimization study of station track utilization in high-speed railroad based on constraints of control in random origin and process
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作者 Yajing Zheng Dekun Zhang 《Railway Sciences》 2024年第3期332-343,共12页
Purpose-The purpose of this paper is to eliminate the fluctuations in train arrival and departure times caused by skewed distributions in interval operation times.These fluctuations arise from random origin and proces... Purpose-The purpose of this paper is to eliminate the fluctuations in train arrival and departure times caused by skewed distributions in interval operation times.These fluctuations arise from random origin and process factors during interval operations and can accumulate over multiple intervals.The aim is to enhance the robustness of high-speed rail station arrival and departure track utilization schemes.Design/methodologylapproach-To achieve this objective,the paper simulates actual train operations,incorporating the fluctuations in interval operation times into the utilization of arrival and departure tracks at the station.The Monte Carlo simulation method is adopted to solve this problem.This approach transforms a nonlinear model,which includes constraints from probability distribution functions and is difficult to solve directly,into a linear programming model that is easier to handle.The method then linearly weights two objectives to optimize the solution.Findings-Through the application of Monte Carlo simulation,the study successfully converts the complex nonlinear model with probability distribution function constraints into a manageable linear programming model.By continuously adjusting the weighting coefficients of the linear objectives,the method is able to optimize the Pareto solution.Notably,this approach does not require extensive scene data to obtain a satisfactory Pareto solution set.Originality/value-The paper contributes to the field by introducing a novel method for optimizing high-speed rail station arrival and departure track utilization in the presence of fluctuations in interval operation times.The use of Monte Carlo simulation to transform the problem into a tractable linear programming model represents a significant advancement.Furthermore,the method's ability to produce satisfactory Pareto solutions without relying on extensive data sets adds to its practical value and applicability in real-world scenarios. 展开更多
关键词 Control in random origin Control in random process High-speed railroad station Arrival and departure track utilization Optimization Paper type Research paper
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Comprehensive Utilization and Control Measures of Iron and Steel Slag
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作者 Xianzhen Wu Jin Xue 《Frontiers of Metallurgical Industry》 2024年第2期52-58,共7页
With the increase of steel production,the amount of steel slag piled up is on the rise.The article analyzes the current situation of blast furnace slag utilization,elaborates on the current treatment technology of bla... With the increase of steel production,the amount of steel slag piled up is on the rise.The article analyzes the current situation of blast furnace slag utilization,elaborates on the current treatment technology of blast furnace slag,and points out that in the future,the utilization of blast furnace slag will develop towards the direction of developing high value-added products,and the sensible heat recovery rate of blast furnace slag is expected to increase.Analyze the current application status and treatment process of converter slag.The comprehensive treat-ment technology of converter slag is limited by multiple factors,and it is proposed to control converter slag from the production source through"slag recycling". 展开更多
关键词 blast furnace slag converter slag comprehensive utilization
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Dietary supplementation with xylooligosaccharides and exogenous enzyme improves milk production,energy utilization efficiency and reduces enteric methane emissions of Jersey cows 被引量:1
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作者 Lifeng Dong Lei Zhao +5 位作者 Bowei Li Yanhua Gao Tianhai Yan Peter Lund Zhuofan Liu Qiyu Diao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第6期2514-2524,共11页
Background Sustainable strategies for enteric methane(CH_(4))mitigation of dairy cows have been extensively explored to improve production performance and alleviate environmental pressure.The present study aimed to in... Background Sustainable strategies for enteric methane(CH_(4))mitigation of dairy cows have been extensively explored to improve production performance and alleviate environmental pressure.The present study aimed to investigate the effects of dietary xylooligosaccharides(XOS)and exogenous enzyme(EXE)supplementation on milk production,nutrient digestibility,enteric CH_(4) emissions,energy utilization efficiency of lactating Jersey dairy cows.Forty-eight lactating cows were randomly assigned to one of 4 treatments:(1)control diet(CON),(2)CON with 25 g/d XOS(XOS),(3)CON with 15 g/d EXE(EXE),and(4)CON with 25 g/d XOS and 15 g/d EXE(XOS+EXE).The 60-d experimental period consisted of a 14-d adaptation period and a 46-d sampling period.The enteric CO_(2)and CH_(4) emissions and O2 consumption were measured using two GreenFeed units,which were further used to determine the energy utilization efficiency of cows.Results Compared with CON,cows fed XOS,EXE or XOS+EXE significantly(P<0.05)increased milk yield,true protein and fat concentration,and energy-corrected milk yield(ECM)/DM intake,which could be reflected by the significant improvement(P<0.05)of dietary NDF and ADF digestibility.The results showed that dietary supplementation of XOS,EXE or XOS+EXE significantly(P<0.05)reduced CH_(4) emission,CH_(4)/milk yield,and CH_(4)/ECM.Furthermore,cows fed XOS demonstrated highest(P<0.05)metabolizable energy intake,milk energy output but lowest(P<0.05)of CH_(4) energy output and CH_(4) energy output as a proportion of gross energy intake compared with the remaining treatments.Conclusions Dietary supplementary of XOS,EXE or combination of XOS and EXE contributed to the improvement of lactation performance,nutrient digestibility,and energy utilization efficiency,as well as reduction of enteric CH_(4) emissions of lactating Jersey cows.This promising mitigation method may need further research to validate its long-term effect and mode of action for dairy cows. 展开更多
关键词 Energy utilization efficiency Enteric methane emissions Exogenous enzyme Jersey cows XYLOOLIGOSACCHARIDES
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An Integrated Framework for Geothermal Energy Storage with CO_(2)Sequestration and Utilization 被引量:2
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作者 Yueliang Liu Ting Hu +7 位作者 Zhenhua Rui Zheng Zhang Kai Du Tao Yang Birol Dindoruk Erling Halfdan Stenby Farshid Torabi Andrey Afanasyev 《Engineering》 SCIE EI CAS CSCD 2023年第11期121-130,共10页
Subsurface geothermal energy storage has greater potential than other energy storage strategies in terms of capacity scale and time duration.Carbon dioxide(CO_(2))is regarded as a potential medium for energy storage d... Subsurface geothermal energy storage has greater potential than other energy storage strategies in terms of capacity scale and time duration.Carbon dioxide(CO_(2))is regarded as a potential medium for energy storage due to its superior thermal properties.Moreover,the use of CO_(2)plumes for geothermal energy storage mitigates the greenhouse effect by storing CO_(2)in geological bodies.In this work,an integrated framework is proposed for synergistic geothermal energy storage and CO_(2)sequestration and utilization.Within this framework,CO_(2)is first injected into geothermal layers for energy accumulation.The resultant high-energy CO_(2)is then introduced into a target oil reservoir for CO_(2)utilization and geothermal energy storage.As a result,CO_(2)is sequestrated in the geological oil reservoir body.The results show that,as high-energy CO_(2)is injected,the average temperature of the whole target reservoir is greatly increased.With the assistance of geothermal energy,the geological utilization efficiency of CO_(2)is higher,resulting in a 10.1%increase in oil displacement efficiency.According to a storage-potential assessment of the simulated CO_(2)site,110 years after the CO_(2)injection,the utilization efficiency of the geological body will be as high as 91.2%,and the final injection quantity of the CO_(2)in the site will be as high as 9.529×10^(8)t.After 1000 years sequestration,the supercritical phase dominates in CO_(2)sequestration,followed by the liquid phase and then the mineralized phase.In addition,CO_(2)sequestration accounting for dissolution trapping increases significantly due to the presence of residual oil.More importantly,CO_(2)exhibits excellent performance in storing geothermal energy on a large scale;for example,the total energy stored in the studied geological body can provide the yearly energy supply for over 3.5×10^(7) normal households.Application of this integrated approach holds great significance for large-scale geothermal energy storage and the achievement of carbon neutrality. 展开更多
关键词 Geothermal energy storage CO_(2)sequestration Carbon neutrality LARGE-SCALE CO_(2)utilization
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Branched fibrous amidoxime adsorbent with ultrafast adsorption rate and high amidoxime utilization for uranium extraction from seawater 被引量:1
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作者 Wan-Ning Ren Xin-Xin Feng +5 位作者 Yu-Long He Ming-Lei Wang Wan-Feng Hong Hong-Wei Han Jiang-Tao Hu Guo-Zhong Wu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第6期79-90,共12页
Direct collection of uranium from low uranium systems via adsorption remains challenging.Fibrous sorbent materials with amidoxime(AO)groups are promising adsorbents for uranium extraction from seawater.However,low AO ... Direct collection of uranium from low uranium systems via adsorption remains challenging.Fibrous sorbent materials with amidoxime(AO)groups are promising adsorbents for uranium extraction from seawater.However,low AO adsorption group utilization remains an issue.We herein fabricated a branched structure containing AO groups on polypropylene/polyethylene spun-laced nonwoven(PP/PE SNW)fibers using grafting polymerization induced by radiation(RIGP)to improve AO utilization.The chemical structures,thermal properties,and surface morphologies of the raw and treated PP/PE SNW fibers were studied.The results show that an adsorptive functional layer with a branching structure was successfully anchored to the fiber surface.The adsorption properties were investigated using batch adsorption experiments in simulated seawater with an initial uranium concentration of 500μg·L^(−1)(pH 4,25℃).The maximum adsorption capacity of the adsorbent material was 137.3 mg·g^(−1)within 24 h;moreover,the uranyl removal reached 96%within 240 min.The adsorbent had an AO utilization rate of 1/3.5 and was stable over a pH range of 4–10,with good selectivity and reusability,demonstrating its potential for seawater uranium extraction. 展开更多
关键词 Radiation graft technology Branching structure High amidoxime utilization Seawater uranium extraction Ultrafast adsorption
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Phosphorylation regulation of nitrogen,phosphorus,and potassium uptake systems in plants
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作者 Dongli Hao Xiaohui Li +4 位作者 Weiyi Kong Rongrong Chen Jianxiu Liu Hailin Guo Jinyan Zhou 《The Crop Journal》 SCIE CSCD 2023年第4期1034-1047,共14页
The uptake of ammonium,nitrate,phosphorus,and potassium ions by roots is mediated by specific ion transporter or channel proteins,and protein phosphorylation regulation events occurring on these proteins and their reg... The uptake of ammonium,nitrate,phosphorus,and potassium ions by roots is mediated by specific ion transporter or channel proteins,and protein phosphorylation regulation events occurring on these proteins and their regulators determine their ultimate activity.Elucidating the mechanism by which protein phosphorylation modification regulates nutrient uptake will advance plant breeding for high nutrientuse efficiency.In this review,it is concluded that the root nutrient absorption system is composed of several,but not all,members of a specific ion transporter or channel family.Under nutrient-starvation conditions,protein phosphorylation-based regulation of these proteins and associated transcription factors increases ion transporter-or channel-mediated nutrient uptake capacity via direct function activity enhancement,allowing more protein trafficking to the plasma membrane,by strengthening the interaction of transporters and channels with partner proteins,by increasing their protein stability,and by transcriptional activation.Under excessive nutrient conditions,protein phosphorylation-based regulation suppresses nutrient uptake by reversing these processes.Strengthening phosphorylation regulation items that increase nutrient absorption and weakening phosphorylation modification items that are not conducive to nutrient absorption show potential as strategies for increasing nutrient use efficiency. 展开更多
关键词 Ammonium uptake machinery Nitrate uptake machinery Phosphate uptake machinery Potassium uptake machinery Transcription factors Protein phosphorylation
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“Extreme utilization” theory and practice in gas storages with complex geological conditions 被引量:1
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作者 MA Xinhua ZHENG Dewen +1 位作者 DING Guosheng WANG Jieming 《Petroleum Exploration and Development》 SCIE 2023年第2期419-432,共14页
Based on more than 20-year operation of gas storages with complex geological conditions and a series of research findings, the pressure-bearing dynamics mechanism of geological body is revealed. With the discovery of ... Based on more than 20-year operation of gas storages with complex geological conditions and a series of research findings, the pressure-bearing dynamics mechanism of geological body is revealed. With the discovery of gas-water flowing law of multi-cycle relative permeability hysteresis and differential utilization in zones, the extreme utilization theory targeting at the maximum amount of stored gas, maximum injection-production capacity and maximum efficiency in space utilization is proposed to support the three-in-one evaluation method of the maximum pressure-bearing capacity of geological body, maximum well production capacity and maximum peak shaving capacity of storage space. This study realizes the full potential of gas storage(storage capacity) at maximum pressure, maximum formation-wellbore coordinate production, optimum well spacing density match with finite-time unsteady flow, and peaking shaving capacity at minimum pressure, achieving perfect balance between security and capacity. Operation in gas storages, such as Hutubi in Xinjiang, Xiangguosi in Xinan, and Shuang6 in Liaohe, proves that extreme utilization theory has promoted high quality development of gas storages in China. 展开更多
关键词 underground gas storage gas-storage geological body maximum pressure-bearing maximum well production capacity maximum peak shaving capacity extreme utilization theory multi-cycle relative permeability hysteresis
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COVID-19 vaccine uptake and its determinants among teenagers and their parents in Zhejiang, China: An online cross-sectional study
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作者 Yu Huang Qingqing Wu +5 位作者 Shuiyang Xu Xiang Zhao Lei Wang Qiaohong Lv Suxian Wu Xuehai Zhang 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2023年第4期176-186,共11页
Objective:To examine COVID-19 vaccine uptake and its determinants among teenagers and their parents in Zhejiang,China.Methods:An online cross-sectional study was conducted among parents of teenagers in Zhejiang,China ... Objective:To examine COVID-19 vaccine uptake and its determinants among teenagers and their parents in Zhejiang,China.Methods:An online cross-sectional study was conducted among parents of teenagers in Zhejiang,China from May 1 to 31,2022.Data were interpreted via univariate and multivariate analyses using the statistical package for the social sciences(SPSS)program.Results:A total of 11115(96.11%)participants and 11449(99.00%)of their children in Zhejiang,China had been vaccinated against COVID-19.Children whose parents did not receive COVID-19 vaccination were 19 times(aOR 18.96,95%CI 12.36-29.08)more likely to be unvaccinated than their counterparts.In addition,children with no previous influenza vaccination,those whose parents doubted the COVID-19 vaccine’s safety or effectiveness,were 6.11 times(aOR 6.11,95%CI 2.80-13.34),8.27 times(aOR 8.27,95%CI 5.33-12.83),and 2.69 times(aOR 2.69,95%CI 1.11-6.50)more likely to be unvaccinated than their counterparts,respectively.COVID-19 vaccine uptake varied between different sociodemographic groups.However,the odds of receiving the COVID-19 vaccine decreased as age and education level increased.The main refusal reasons claimed by participants were that they had medical conditions that may not qualify them for vaccination(53.78%),followed by safety concerns about the vaccine(13.56%),not knowing where to get vaccinated(6.44%),and concerns about fertility issues(5.56%).Conclusions:Despite a highly encouraging level of COVID-19 vaccine uptake in Zhejiang,China,the elderly and highly educated people had lower COVID-19 vaccine uptake.It is suggested that tailored health education strategies should be taken to increase the COVID-19 vaccine uptake in such groups.Furthermore,with vaccination rates at such a high level,the pandemic is still ongoing,and public confidence in vaccines may decline.Thus,sufficient evidence-based information regarding COVID-19 vaccines should be provided to the public. 展开更多
关键词 COVID-19 Vaccine uptake China TEENAGERS PARENTS
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Uptake of Two Doses of HPV Vaccines in Nakuru County, Kenya: A Case of Rongai and Nakuru West Sub-Counties
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作者 Tabitha Chepkemoi Phylis Jerotich 《Journal of Biosciences and Medicines》 CAS 2023年第1期1-7,共7页
Background: HPV vaccines were introduced globally as one of the most effective strategies to prevent cervical cancer. HPV vaccines were rolled out in Kenya in 2019 targeting girls aged 10 - 14 years, but the uptake ha... Background: HPV vaccines were introduced globally as one of the most effective strategies to prevent cervical cancer. HPV vaccines were rolled out in Kenya in 2019 targeting girls aged 10 - 14 years, but the uptake has not been satisfactory. The Purpose of the Study: The aim of the study was to assess the level of HPV uptake among girls aged 10 - 14 years in Rongai and Nakuru West Sub-Counties in Nakuru County. Method: This was a cross-sectional study where data on HPV uptake was retrieved from all the public health facilities located in Rongai and Nakuru West Sub-Counties, Nakuru County, entered into Microsoft Excel then transferred to SPSS version 26 for analysis of HPV vaccine uptake since the year 2019 to June 2022. Data Analysis: Descriptive statistics were used where tables and graphs were generated to represent the percentages and trends of HPV vaccine uptake. Results: The average percentage of HPV uptake in Nakuru West Sub-County since the rollout of vaccination was 17% while that of Rongai Sub-County was 15%. In 2019, HPV 1 uptake was generally low for both Sub-Counties, the results show no HPV 2 vaccines were administered during that year. In 2020, Nakuru West reported an increase in HPV 1 uptake, while Rongai reported a drop in HPV 1 uptake. Both Sub-Counties reported an increase in HPV 2 in 2020 as compared to the previous year. The highest HPV 1 & 2 uptakes were reported in 2021 in both Sub-Counties. The uptake of both HPV 1 & 2 kept increasing subsequently. Conclusion: The overall uptake of HPV vaccines for Doses 1 and 2, in both Rongai and Nakuru West Sub-Counties, is low. However, there has been a consistent increase in uptake of the two doses in the two Sub-Counties since 2019. Therefore, raising public awareness of the importance of HPV vaccination could improve uptake. 展开更多
关键词 Cervical Cancer Huma Papilloma Virus HPV Vaccines HPV Vaccines uptake Girls Aged 10 - 14 Years
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Comparison of growth and nutrient uptake capacities of three dominant species of Qinhuangdao green tides
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作者 Hongbin Han Ruobing Wen +1 位作者 Hui Wang Sheng Zhao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第4期114-123,共10页
Since 2015, green tides have been blooming in offshore waters of Qinhuangdao, with serious impacts on the local ecological environment and tourism. Ulva australis, Bryopsis plumosa, and U. prolifera are the dominant s... Since 2015, green tides have been blooming in offshore waters of Qinhuangdao, with serious impacts on the local ecological environment and tourism. Ulva australis, Bryopsis plumosa, and U. prolifera are the dominant species of Qinhuangdao green tides, following a sequential succession pattern. Ulva prolifera is the dominant species,with the highest biomass and the greatest influence on the local ecological environment. To study the reason of green tide dominant species succession and U. profilera became the dominant species with the largest biomass,we compared and analyzed the growth and nutrient uptake capacity of the three algae. The results showed that temperature significantly affects the growth of the three species. Within the temperature range of the experimental setup, the optimum temperature for the growth of U. australis, B. plumosa and U. profilera is10℃, 15℃, and 20–25℃, respectively. Combined with the temperature variation trend during green tide bloom development, we believe that temperature is the key environmental factor for the succession of the dominant species. Ulva prolifera has a higher growth rate than U. australis and B. plumosa under the same nitrate,ammonium, and phosphate levels. Significant differences in the maximum absorption rate(R_(max)) and R_(max)/Ks(the relationship between uptake rate and substrate concentration) values indicated that U. prolifera had an apparent competitive advantage over U. australis and B. plumosa regarding nutrient uptake. Therefore, the strong growth and nutrient uptake capacities of U. prolifera might be the main reason for becoming the dominant species with the largest biomass in Qinhuangdao green tides. 展开更多
关键词 GROWTH nutrient uptake dominant specie green tide Qinhuangdao
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