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The Mechanism of Heating Rate on the Secondary Recrystallization Evolution in Grain Oriented Silicon Steel
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作者 GAO Qian LI Jun +3 位作者 WANG Xianhui CAO Laifu GONG Jian LI Bo 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期275-282,共8页
Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the... Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the Zener factor,the diameter and number density of precipitates of interrupted testing samples were statistically calculated.The effect of precipitate ripening on the Goss texture and magnetic property was investigated.Data indicated that the trend of Zener factor was similar under different heating rates,first increasing and then decreasing,and that the precipitate maturing was greatly inhibited as the heating rate increased.Secondary recrystallization was developed at the temperature of 1010℃when a heating rate of 5℃/h was used,resulting in Goss,Brass and{110}<227>oriented grains growing abnormally and a magnetic induction intensity of 1.90T.Furthermore,increasing the heating rate to 20℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss texture.However,when the heating rate was extremely fast,such as 40℃/h,poor secondary recrystallization was developed with many island grains,corresponding to a decrease in magnetic induction intensity to 1.87 T.At a suitable heating rate of 20℃/h,the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1020℃were found among the experimental variables in this study.The heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates,leading to the deviation and dispersion of Goss texture,thereby reducing the magnetic properties. 展开更多
关键词 high temperature annealing heating rate secondary recrystallization grain oriented silicon steel
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Glomerular filtration rate and comorbidity factors in elderly hospitalizations
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作者 Hatice Hamarat 《World Journal of Nephrology》 2025年第1期93-98,共6页
BACKGROUND With an increase in the elderly population,the frequency of hospitalizations in recent years has also risen at a rapid pace.This,in turn,has resulted in poor outcomes and costly treatments.Hospitalization r... BACKGROUND With an increase in the elderly population,the frequency of hospitalizations in recent years has also risen at a rapid pace.This,in turn,has resulted in poor outcomes and costly treatments.Hospitalization rates increase in elderly patients due to a decline in glomerular filtration rate(GFR).AIM To investigate the connection between GFR and comorbidity and reasons for hospitalization in elderly patients.METHODS We analyzed patients aged 75 years and over who were admitted to the internal medicine clinic of a tertiary hospital in Eskisehir.At admission,we calculated GFR values using the Modification of Diet in Renal Disease study formula and classified them into six categories:G1,G2,G3a,G3b,G4,and G5.We analyzed associations with hospitalization diagnoses and comorbidity factors.RESULTS The average age of the patients was 80.8 years(±4.5 years).GFR was 57.287±29.5 mL/kg/1.73 m2 in women and 61.3±31.5 mL/kg/1.73 m2 in men(P=0.106).Most patients were admitted to the hospital at G2 stage(32.8%).The main reasons for hospitalization were anemia(34.4%and 28.6%)and malnutrition(20.9%and 20.8%)in women and men,respectively(P=0.078).The most frequent comor-bidity leading to hospitalization was arterial hypertension(n=168,28%),fo-llowed by diabetes(n=166,27.7%)(P=0.001).CONCLUSION When evaluating geriatric patients,low GFR alone does not provide sufficient information.Patients’comorbid factors should also be taken into account.There is no association between low GFR during hospitalization and hospitalization-Hamarat H.Aging and GFR related diagnoses.Knowing the GFR value before hospitalization will be more informative in such studies. 展开更多
关键词 AGING Glomerular filtration rate HOSPITALIZATION COMORBIDITY Elderly hospitalizations
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Text-and-Timbre-Based Speech Semantic Coding for Ultra-Low-Bitrate Communications
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作者 Yang Xiaoniu Qian Liping +2 位作者 Lyu Sikai Wang Qian WangWei 《China Communications》 2025年第1期7-24,共18页
To address the contradiction between the explosive growth of wireless data and the limited spectrum resources,semantic communication has been emerging as a promising communication paradigm.In this paper,we thus design... To address the contradiction between the explosive growth of wireless data and the limited spectrum resources,semantic communication has been emerging as a promising communication paradigm.In this paper,we thus design a speech semantic coded communication system,referred to as Deep-STS(i.e.,Deep-learning based Speech To Speech),for the lowbandwidth speech communication.Specifically,we first deeply compress the speech data through extracting the textual information from the speech based on the conformer encoder and connectionist temporal classification decoder at the transmitter side of Deep-STS system.In order to facilitate the final speech timbre recovery,we also extract the short-term timbre feature of speech signals only for the starting 2s duration by the long short-term memory network.Then,the Reed-Solomon coding and hybrid automatic repeat request protocol are applied to improve the reliability of transmitting the extracted text and timbre feature over the wireless channel.Third,we reconstruct the speech signal by the mel spectrogram prediction network and vocoder,when the extracted text is received along with the timbre feature at the receiver of Deep-STS system.Finally,we develop the demo system based on the USRP and GNU radio for the performance evaluation of Deep-STS.Numerical results show that the ac-Received:Jan.17,2024 Revised:Jun.12,2024 Editor:Niu Kai curacy of text extraction approaches 95%,and the mel cepstral distortion between the recovered speech signal and the original one in the spectrum domain is less than 10.Furthermore,the experimental results show that the proposed Deep-STS system can reduce the total delay of speech communication by 85%on average compared to the G.723 coding at the transmission rate of 5.4 kbps.More importantly,the coding rate of the proposed Deep-STS system is extremely low,only 0.2 kbps for continuous speech communication.It is worth noting that the Deep-STS with lower coding rate can support the low-zero-power speech communication,unveiling a new era in ultra-efficient coded communications. 展开更多
关键词 low coding rate semantic communication speech recognition speech synthesis
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On load dependence of detachment rate of kinesin motor
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作者 Xiao-Xuan Shi Yao Wang +1 位作者 Yu-Ru Liu Ping Xie 《Chinese Physics B》 2025年第1期498-505,共8页
Kinesin is an archetypal microtubule-based molecular motor that can generate force to transport cargo in cells. The load dependence of the detachment rate is an important factor of the kinesin motor, the determination... Kinesin is an archetypal microtubule-based molecular motor that can generate force to transport cargo in cells. The load dependence of the detachment rate is an important factor of the kinesin motor, the determination of which is critically related to the chemomechanical coupling mechanism of the motor. Here, we use three models for the load dependence of the detachment rate of the kinesin motor to study theoretically and numerically the maximal force generated and microtubuleattachment duration of the motor. By comparing the theoretical and numerical results with the available experimental data,we show that only one model can explain well the available experimental data, indicating that only this model can be applicable to the kinesin motor. 展开更多
关键词 KINESIN detachment rate generated force chemomechanical coupling mechanism optical trapping
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Effect of comprehensive perioperative nursing on pain intensity,complication rates,and comfort levels in patients undergoing gallstone surgery
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作者 Chen-Yan Bao Xiao-Kun Ding +2 位作者 Qiao-Fei Qi Peng Ye Ze-Jun Fang 《World Journal of Gastrointestinal Surgery》 2025年第2期111-119,共9页
BACKGROUND Surgery is the gold standard for gallstone treatment.Nevertheless,the complications associated with the surgical procedure can exert diverse and adverse impacts on patients’health and quality of life to va... BACKGROUND Surgery is the gold standard for gallstone treatment.Nevertheless,the complications associated with the surgical procedure can exert diverse and adverse impacts on patients’health and quality of life to varying extents.Hence,it is essential to offer perioperative care to patients undergoing gallstone surgery.AIM To examine the impact of perioperative comprehensive nursing on pain intensity,complication rates,and patient comfort in individuals undergoing gallstone surgery.METHODS From February 2022 to February 2024,195 patients who underwent gallstone surgery at Sanmen People’s Hospital were selected and divided into two groups:A control group receiving routine nursing care(95 patients)and a research group receiving perioperative comprehensive nursing(100 patients).Key postoperative recovery indicators,including time to first postoperative anal exhaust,oral food intake,and ambulation,were observed,along with pain intensity(measured by the numeric rating scale),complication rate(bleeding,incision infection,recurrence),patient comfort(assessed using the visual analogue scale),and quality of life(measured by the World Health Organization Quality of Life-BREF).RESULTS The research group showed significantly shorter times to first postoperative anal exhaust,oral intake,and ambulation.Moreover,numeric rating scale pain scores in the research group were markedly lower post-nursing,and the total complication rate was significantly reduced compared to the control group.Furthermore,comfort levels improved considerably in the research group,and World Health Organization Quality of Life-BREF scores across the physical,psychological,social,and environmental domains were significantly higher compared to the control group following nursing care.CONCLUSION Perioperative comprehensive nursing effectively enhances postoperative recovery in patients undergoing gallstone surgery,reducing pain,lowering complications,and improving patient comfort and quality of life,which deserves clinical application. 展开更多
关键词 Perioperative comprehensive nursing Gallstone surgery Pain intensity Complication rate COMFORT
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Thermal effects on the strain rate-dependent behavior of highly compacted GMZ01 bentonite
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作者 Pengju Qin Weimin Ye +1 位作者 Qiong Wang Yonggui Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第1期453-464,共12页
Investigation of thermal effects on the strain rate-dependent properties of compacted bentonite is crucial for the long-term safety assessment of deep geological repository for disposal of high-level radioactive waste... Investigation of thermal effects on the strain rate-dependent properties of compacted bentonite is crucial for the long-term safety assessment of deep geological repository for disposal of high-level radioactive waste.In the present work,cylindrical GMZ01 bentonite specimens were compacted with suction-controlled by the vapor equilibrium technique.Then,a series of temperature-and suction-controlled stepwise constant rate of strain(CRS)tests was performed and the rate-dependent compressibility behavior of the highly compacted GMZ01 bentonite was investigated.The plastic compressibility parameterλ,the elastic compressibility parameterκ,the yield stress p0,as well as the viscous parameterαwere determined.Results indicate thatλ,κandαdecrease and p0 increases as suction increases.Upon heating,parametersλ,αand p0 decrease.It is also found that p0 increases linearly with increasing CRS in a double-logarithm coordinate.Based on the experimental results,a viscosity parameterα(s,T)was fitted to capture the effects of suction s and temperature T on the relationship between yield stress and strain rate.Then,an elastic-thermo-viscoplastic model for unsaturated soils was developed to describe the thermal effects on the rate-dependent behavior of highly compacted GMZ01 bentonite.Validation showed that the calculated results agreed well to the measured ones. 展开更多
关键词 Highly compacted bentonite rate-dependent behavior Constant rate of strain Temperature Elastic-thermo-viscoplastic model
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Study on discharge characteristics of low-temperature sub-atmospheric pressure under steep change rate voltage
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作者 Bo ZHU Ximu HAN +2 位作者 He SU Xiangjie MA Guoyan WU 《Plasma Science and Technology》 2025年第1期52-61,共10页
Aiming at the gas discharge problem in electric aircraft,this work studies the gas discharge characteristics at low-temperature sub-atmospheric pressure.A gas discharge shooting platform was built,and the discharge pr... Aiming at the gas discharge problem in electric aircraft,this work studies the gas discharge characteristics at low-temperature sub-atmospheric pressure.A gas discharge shooting platform was built,and the discharge process was photographed by intensified charge-coupled device(ICCD).A two-dimensional axisymmetric model of needle-plate electrode gas discharge was established,and three sets of Helmholtz equations were used to solve the photoionization.The results show that under the same voltage,the electric field intensity in the discharge process increases first,then decreases and finally increases again.The discharge speed increases with the increase of altitude,and the electron density in the streamer decreases with the increase of altitude.The development speed of the streamer in the middle stage is higher than that in the early stage,and the speed increases more obviously with the increase of altitude.The development speed of the streamer in the later stage is lower than that in the middle stage,but with the increase of altitude,the development speed of the streamer in the later stage is higher than that in the middle stage. 展开更多
关键词 electric aircraft gas discharge steep change rate voltage electric field intensity electron density
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Longitudinal assessment of measured and estimated glomerular filtration-rate in autosomal dominant polycystic kidney disease:Real practice experience
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作者 Juan M Fernandez JoséC Rodriguez-Pérez +3 位作者 M Mercedes Lorenzo-Medina Fancisco Rodriguez-Esparragon Juan C Quevedo-Reina Carmen R Hernandez-Socorro 《World Journal of Nephrology》 2025年第1期99-109,共11页
BACKGROUND Equations for estimation glomerular filtration rate(eGFR)have been associated with poor clinical performance and their clinical accuracy and reliability have been called into question.AIM To assess the long... BACKGROUND Equations for estimation glomerular filtration rate(eGFR)have been associated with poor clinical performance and their clinical accuracy and reliability have been called into question.AIM To assess the longitudinal changes in measured glomerular filtration rate(mGFR)in patients with autosomal dominant polycystic kidney disease(ADPKD).METHODS Analysis of an ambispective data base conducted on consecutive patients diagnosed with ADPKD.The mGFR was assessed by iohexol clearance;while eGFR was calculated by three different formulas:(1)The chronic kidney disease epidemiology collaboration(CKD-EPI);(2)Modification of diet in renal disease(MDRD);and(3)The 24-hour urine creatinine clearance(CrCl).The primary end-points were the mean change in mGFR between the baseline and final visit,as well as the comparison of the mean change in mGFR with the change estimated by the different formulas.RESULTS Thirty-seven patients were included in the study.As compared to baseline,month-6 mGFR was significantly decrease by-4.4 mL/minute±10.3 mL/minute(P=0.0132).However,the CKD-EPI,MDRD,and CrCl formulas underestimated this change by 48.3%,89.0%,and 45.8%respectively,though none of these differences reached statistical significance(P=0.3647;P=0.0505;and P=0.736,respectively).The discrepancies between measured and estimated glomerular filtration rate values,as evaluated by CKD-EPI(r=0.29,P=0.086);MDRD(r=0.19,P=0.272);and CrCl(r=0.09,P=0.683),were not correlated with baseline mGFR values.CONCLUSION This study indicated that eGFR inaccurately reflects the decline in mGFR and cannot reliably track changes over time.This poses significant challenges for clinical decision-making,particularly in treatment strategies. 展开更多
关键词 Autosomal dominant polycystic kidney disease Glomerular filtration rate End-stage kidney disease IOHEXOL Chronic kidney disease epidemiology collaboration Modification of diet in renal disease
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QSAR for Predicting Biodegradation Rates of Polycyclic Aromatic Hydrocarbons in Aqueous Systems 被引量:3
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作者 徐香 李先国 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第8期1212-1221,共10页
The relationship between chemical structures and biodegradation rates (k b) of 22 polycyclic aromatic hydrocarbons (PAHs) was studied using density functional theory (DFT) and stepwise multiple linear regression... The relationship between chemical structures and biodegradation rates (k b) of 22 polycyclic aromatic hydrocarbons (PAHs) was studied using density functional theory (DFT) and stepwise multiple linear regression analysis (SMLR) method.The equilibrium geometries and vibration frequency have been investigated at the B3LYP/6-31+G(d,p) level by thinking Solvent effects using a selfconsistent reaction field (SCRF) based on the polarizable continuum model (PCM).It was concluded that the biodegradation rate was closely related to its molecular structure,and there is one high correlation coefficient between the in-plane bending vibration frequency of the conjugated ring of PAHs (Freq) and k b.By means of regression analysis,the main factors affecting the biodegradation rate were obtained and the equation of quantitative structure-activity relationship (QSAR) was successfully established kb =-0.653+0.001Freq+0.068CQ+0.049N1.Statistical evaluation of the developed QSAR showed that the relationships were statistically significant and the model had good predictive ability.The fact that a bending frequency is more important than the HOMO or LUMO energies in predicting k b suggests that the bending of benzene ring might play an important role in the enzymatic catalysis of the initial oxidation step. 展开更多
关键词 quantitative structure-activity relationships polycyclic aromatic hydrocarbons density functional theory biodegradation rate
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QSBR Study on the Biodegradation Rate Constant of Chloro-phenol Compounds 被引量:2
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作者 陈怡君 王遵尧 +1 位作者 毛亮 高士祥 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第6期895-899,共5页
Structural and thermodynamic parameters of 16 chloro-phenol compounds in water solution were calculated and fully optimized by using Onsager model in self-consistent reaction field(SCRF) based on the B3LYP/6-311G*... Structural and thermodynamic parameters of 16 chloro-phenol compounds in water solution were calculated and fully optimized by using Onsager model in self-consistent reaction field(SCRF) based on the B3LYP/6-311G** level.These quantum chemical parameters were used as theoretical descriptors to correlate with the experimental biodegradation rate constant(Kb) of 16 compounds by stepwise multiple linear regression.As a result,a three-parameter model including molecular average polarizability(α),entropy(Sθ),and molar heat capacity at constant volume(CVθ) were established for Kb prediction,which was proposed with correlation coefficient R2 = 0.894.α exhibits the most significant effect on Kb.Variance analysis and standard t-value test were applied to validate the model.As expected,this model exhibits good robustness and prediction ability,which can be used in Kb prediction of analogs. 展开更多
关键词 chloro-phenol biodegradation rate constant(Kb) density functional theory(DFT) QSBR
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Anoxic biodegradation of dimethyl phthalate (DMP) by activated sludge cultures under nitrate-reducing conditions 被引量:6
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作者 WU Dong-lei HU Bao-lan ZHENG Ping Qaisar Mahmood 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第10期1252-1256,共5页
Worldwide extensive use of plasticized plastics has resulted in phthalates pollution in different environment. Nitrates from industry and agriculture are also widely disseminated in the soils, natural waters and waste... Worldwide extensive use of plasticized plastics has resulted in phthalates pollution in different environment. Nitrates from industry and agriculture are also widely disseminated in the soils, natural waters and wastewaters. Dimethyl phthalate (DMP) biodegradation by activated sludge cultures under nitrate-reducing conditions was investigated. Under one optimized condition, DMP was biodegraded from 102.20 mg/L to undetectable level in 56 h under anoxic conditions and its reaction fitted well with the first-order kinetics. Using the high-performance liquid chromatography (HPLC) and liquid chromatography mass spectrometry (LC-MS) analysis, mono-methyl phthalate (MMP) and phthalic acid (PA) were detected as the major intermediates of DMP biodegradation. When combined with the determination of chemical oxygen demand (CODer) removal capacity and pH, DMP was found to be mineralized completely under anoxic conditions. The biodegradation pathway was proposed as DMP → MMP→ PA→…→ CO2 + H2O. The molar ratio of DMP to nitrate consumed was found to be 9.0:1, which agrees well with the theoretical stoichiometric values of DMP biodegradation by nitrate-reducing bacteria. The results of the non-linear simulation showed that the optimum pH and temperature for the degradation were 7.56 and 31.4℃, respectively. 展开更多
关键词 biodegradation dimethyl phthalate phthalic acid nitrate reduction MINERALIZATION
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3D printing of calcium phosphate bioceramic with tailored biodegradation rate for skull bone tissue reconstruction 被引量:7
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作者 Boqing Zhang Huan Sun +6 位作者 Lina Wu Liang Ma Fei Xing Qingquan Kong Yujiang Fan Changchun Zhou Xingdong Zhang 《Bio-Design and Manufacturing》 SCIE CSCD 2019年第3期161-171,共11页
The bone regenerative scaffold with the tailored degradation rate matching with the growth rate of the new bone is essential for adolescent bone repair.To satisfy these requirement,we proposed bone tissue scaffolds wi... The bone regenerative scaffold with the tailored degradation rate matching with the growth rate of the new bone is essential for adolescent bone repair.To satisfy these requirement,we proposed bone tissue scaffolds with controlled degradation rate using osteoinductive materials(Ca-P bioceramics),which is expected to present a controllable biodegradation rate for patients who need bone regeneration.Physicochemical properties,porosity,compressive strength and degradation properties of the scaffolds were studied.3D printed Ca-P scaffold(3DS),gas foaming Ca-P scaffold(FS)and autogenous bone(AB)were used in vivo for personalized beagle skull defect repair.Histological results indicated that the 3DS was highly vascularized and well combined with surrounding tissues.FS showed obvious newly formed bone tissues.AB showed the best repair effect,but it was found that AB scaffolds were partially absorbed and degraded.This study indicated that the 3D printed Ca-P bioceramics with tailored biodegradation rate is a promising candidate for personalized skull bone tissue reconstruction. 展开更多
关键词 3D printing SKULL repair Calcium PHOSPHATE ceramics TAILORED biodegradation rate Bone RECONSTRUCTION
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Anaerobic benzene biodegradation by a pure bacterial culture of Bacillus cereus under nitrate reducing conditions 被引量:7
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作者 Junfeng Dou Aizhong Ding +3 位作者 Xiang Liu Yongchao Du Dong Deng Jinsheng Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第5期709-715,共7页
A pure culture using benzene as sole carbon and energy sources was isolated by screening procedure from gasoline contaminated soil.The analysis of the 16S rDNA gene sequence,morphological and physiological characteris... A pure culture using benzene as sole carbon and energy sources was isolated by screening procedure from gasoline contaminated soil.The analysis of the 16S rDNA gene sequence,morphological and physiological characteristics showed that the isolated strain was a member of genus Bacillus cereus.The biodegradation performance of benzene by B.cereus was evaluated,and the results showed that benzene could be efficiently biodegraded when the initial benzene concentration was below 150 mg/L.The metabolites of anaerobic nitrate-dependent benzene oxidation by strain B.cereus were identified as phenol and benzoate.The results of substrate interaction between binary combinations for benzene,phenol and benzoate showed that the simultaneous presence of benzene stimulated the degradation of benzoate,whereas the addition of benzene inhibited the degradation of phenol.Benzene degradation by B.cereus was enhanced by the addition of phenol and benzoate,the enhanced effects were more pronounced at higher concentration.To our knowledge,this is the first report that the isolated bacterial culture of B.cereus can efficiently degraded benzene under nitrate reducing conditions. 展开更多
关键词 Bacillus cereus nitrate reduction anaerobic biodegradation substrate interaction PHENOL BENZOATE
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Anaerobic Biodegradation of Tetrachloroethylene with Acetic Acid as Cometabolism Substrate under Anaerobic Condition 被引量:1
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作者 LI Ye LIU Fei +2 位作者 CHEN Honghan SHI Jinhua WANG Yufan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第4期911-916,共6页
A series of batch-type experiments with acetate acid as the primary substrate were performed using enrichment cultures developed from the anaerobic sludge to investigate the effect of acetate acid on tetrachloroethyle... A series of batch-type experiments with acetate acid as the primary substrate were performed using enrichment cultures developed from the anaerobic sludge to investigate the effect of acetate acid on tetrachloroethylene (PCE) biodegradation. Experimental results indicated that acetate acid was an efficient electron donor in affecting the biotransformability of PCE. Trichloroethylene (TCE) was the primary dehalogenation product, and small amounts of dichloroethylenes (DCEs) were also detected. No significant further DCEs degradation was detected. PCE degradation rate in the experiment was 36.6 times faster than background rate in natural groundwater. 展开更多
关键词 biodegradation co-metabolism substrate TETRACHLOROETHYLENE
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A Kinetic Study of Anaerobic Biodegradation of Food and Fruit Residues during Biogas Generation Using Initial Rate Method 被引量:2
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作者 William Wanasolo Samwel Victor Manyele John Makunza 《Engineering(科研)》 2013年第7期577-586,共10页
A kinetic study of biogas production from Urban Solid Waste (USW) generated in Dar es Salaam city (Tanzania) is presented. An experimental bioreactor simulating mesophilic conditions of most USW landfills was develope... A kinetic study of biogas production from Urban Solid Waste (USW) generated in Dar es Salaam city (Tanzania) is presented. An experimental bioreactor simulating mesophilic conditions of most USW landfills was developed. The goal of the study was to generate the kinetic order of reaction with respect to biodegradable organic waste and use it to model biogas production from food residues mixed with fruit waste. Anaerobic biodegradation was employed under temperature range of 28℃ - 38℃. The main controls were leachate recirculation and pH adjustments to minimize acid inhibitory effects and accelerate waste biodegradation. The experimental setup comprised of three sets of bioreactors. A biodegradation rate law in differential form was proposed and the numerical values of kinetic order and rate constant were determined using initial rate method as 0.994 and 0.3093 mol0.006·day-1, respectively. Results obtained were consistent with that found in literature and model predictions were in reasonable agreement with experimental data. 展开更多
关键词 Urban and MUNICIPAL Solid WASTE BIOGAS Production Anaerobic biodegradation MESOPHILIC Conditions Order of Reaction Kinetic Model INITIAL rate Method Renewable Energy BIOREACTOR Landfill Biodegradable Organic WASTE
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Effects of Substrate Permeation on Kinetics of Phenol Biodegradation 被引量:1
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作者 冀秀玲 张金利 +2 位作者 李韡 韩振亭 王一平 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第2期151-155,共5页
Based on the theory of substrate permeation through the cytoplasmic membrane,and considering the effect of initial concentration of substrate,a new kinetic model of phenol degradation process was proposed,Comparing wi... Based on the theory of substrate permeation through the cytoplasmic membrane,and considering the effect of initial concentration of substrate,a new kinetic model of phenol degradation process was proposed,Comparing with the widely used Haldane model,which is greatly dependent on the initial phenol concentration,our model can be used to simulate the phenol degradation process in a wide range of initial phenol concentration by using only one set of model parameters ,Therefore,this new kinetic model has much more potential applications to industrial design and operation. 展开更多
关键词 substrate permeation specific degradation rate PHENOL KINETICS
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Biodegradation of Tetrachlorothylene Using Methanol as Co-metabolic Substrate
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作者 QI YANG HAI-TAO SHANG +2 位作者 Hui-DI LI HONG-BO XI JIAN-LONG WANG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2008年第2期98-102,共5页
Objective To investigate the biodegradation of tetrachloroethylene (PCE) using methanol as electron donor by acclimated anaerobic sludge. Methods HP-6890 gas chromatograph (GC), together with HP-7694 autosarnpler,... Objective To investigate the biodegradation of tetrachloroethylene (PCE) using methanol as electron donor by acclimated anaerobic sludge. Methods HP-6890 gas chromatograph (GC), together with HP-7694 autosarnpler, was used to analyze the concentration of PCE and intermediates. Results PCE could be decholrinated reductively to DCE via TCE, and probably further to VC and ethylene. The degradation of PCE and TCE conformed to first-order reaction kinetics. The reaction rate constants were 0.8991 d^-1 and 0.068 d^-1, respectively, and the corresponding half-life were 0.77 d and 10.19 d, respectively. TCE production rate constant was 0.1333 d^-1, showing that PCE was degraded more rapidly than TCE. Conclusion Methanol is an electron donor suitable for PCE degradation and the cometabolic electron donors are not limiting factors for PCE degradation. 展开更多
关键词 TETRACHLOROETHYLENE Anaerobic cometabolism biodegradation
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BIODEGRADATION OF REGENERATED CELLULOSE FILMS BY FUNGI
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作者 张俐娜 刘海清 +3 位作者 郑连爽 张甲耀 杜予民 柳卫莉 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1996年第4期338-345,共8页
The biodegradability of Aspergillus niger (A. niger), Mucor (M-305) and Trichoderma (T-311) strains on regenerated cellulose films in media was investigated. The results showed that T-311 strain isolated from soil adh... The biodegradability of Aspergillus niger (A. niger), Mucor (M-305) and Trichoderma (T-311) strains on regenerated cellulose films in media was investigated. The results showed that T-311 strain isolated from soil adhered on the cellulose film fragments has stronger degradation effect on the cellulose film than A. niger strain. The weights, molecular weights and tensile strengths of the cellulose films in both shake culture and solid media decreased with incubation time, accompanied by producing CO2 and saccharides. HPLC, IR and released CO2 analysis indicated that the biodegradation products of the regenerated cellulose films mainly contain oligosaccharides, cellobiose, glucose, arabinose, erythrose, glycerose, glycerol, ethanal, formaldehyde and organic acid, the end products were CO2 and water. After a month, the films were completely decomposed by fungi in the media at 30 degrees C. 展开更多
关键词 biodegradation regenerated cellulose film FUNGI MEDIUM
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Prediction model for corrosion rate of low-alloy steels under atmospheric conditions using machine learning algorithms 被引量:3
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作者 Jingou Kuang Zhilin Long 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期337-350,共14页
This work constructed a machine learning(ML)model to predict the atmospheric corrosion rate of low-alloy steels(LAS).The material properties of LAS,environmental factors,and exposure time were used as the input,while ... This work constructed a machine learning(ML)model to predict the atmospheric corrosion rate of low-alloy steels(LAS).The material properties of LAS,environmental factors,and exposure time were used as the input,while the corrosion rate as the output.6 dif-ferent ML algorithms were used to construct the proposed model.Through optimization and filtering,the eXtreme gradient boosting(XG-Boost)model exhibited good corrosion rate prediction accuracy.The features of material properties were then transformed into atomic and physical features using the proposed property transformation approach,and the dominant descriptors that affected the corrosion rate were filtered using the recursive feature elimination(RFE)as well as XGBoost methods.The established ML models exhibited better predic-tion performance and generalization ability via property transformation descriptors.In addition,the SHapley additive exPlanations(SHAP)method was applied to analyze the relationship between the descriptors and corrosion rate.The results showed that the property transformation model could effectively help with analyzing the corrosion behavior,thereby significantly improving the generalization ability of corrosion rate prediction models. 展开更多
关键词 machine learning low-alloy steel atmospheric corrosion prediction corrosion rate feature fusion
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Pulse rate estimation based on facial videos:an evaluation and optimization of the classical methods using both self-constructed and public datasets 被引量:1
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作者 Chao-Yong Wu Jian-Xin Chen +3 位作者 Yu Chen Ai-Ping Chen Lu Zhou Xu Wang 《Traditional Medicine Research》 2024年第1期14-22,共9页
Pulse rate is one of the important characteristics of traditional Chinese medicine pulse diagnosis,and it is of great significance for determining the nature of cold and heat in diseases.The prediction of pulse rate b... Pulse rate is one of the important characteristics of traditional Chinese medicine pulse diagnosis,and it is of great significance for determining the nature of cold and heat in diseases.The prediction of pulse rate based on facial video is an exciting research field for getting palpation information by observation diagnosis.However,most studies focus on optimizing the algorithm based on a small sample of participants without systematically investigating multiple influencing factors.A total of 209 participants and 2,435 facial videos,based on our self-constructed Multi-Scene Sign Dataset and the public datasets,were used to perform a multi-level and multi-factor comprehensive comparison.The effects of different datasets,blood volume pulse signal extraction algorithms,region of interests,time windows,color spaces,pulse rate calculation methods,and video recording scenes were analyzed.Furthermore,we proposed a blood volume pulse signal quality optimization strategy based on the inverse Fourier transform and an improvement strategy for pulse rate estimation based on signal-to-noise ratio threshold sliding.We found that the effects of video estimation of pulse rate in the Multi-Scene Sign Dataset and Pulse Rate Detection Dataset were better than in other datasets.Compared with Fast independent component analysis and Single Channel algorithms,chrominance-based method and plane-orthogonal-to-skin algorithms have a more vital anti-interference ability and higher robustness.The performances of the five-organs fusion area and the full-face area were better than that of single sub-regions,and the fewer motion artifacts and better lighting can improve the precision of pulse rate estimation. 展开更多
关键词 pulse rate heart rate PHOTOPLETHYSMOGRAPHY observation and pulse diagnosis facial videos
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