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High-throughput screening of CO_(2) cycloaddition MOF catalyst with an explainable machine learning model
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作者 Xuefeng Bai Yi Li +3 位作者 Yabo Xie Qiancheng Chen Xin Zhang Jian-Rong Li 《Green Energy & Environment》 SCIE EI CAS 2025年第1期132-138,共7页
The high porosity and tunable chemical functionality of metal-organic frameworks(MOFs)make it a promising catalyst design platform.High-throughput screening of catalytic performance is feasible since the large MOF str... The high porosity and tunable chemical functionality of metal-organic frameworks(MOFs)make it a promising catalyst design platform.High-throughput screening of catalytic performance is feasible since the large MOF structure database is available.In this study,we report a machine learning model for high-throughput screening of MOF catalysts for the CO_(2) cycloaddition reaction.The descriptors for model training were judiciously chosen according to the reaction mechanism,which leads to high accuracy up to 97%for the 75%quantile of the training set as the classification criterion.The feature contribution was further evaluated with SHAP and PDP analysis to provide a certain physical understanding.12,415 hypothetical MOF structures and 100 reported MOFs were evaluated under 100℃ and 1 bar within one day using the model,and 239 potentially efficient catalysts were discovered.Among them,MOF-76(Y)achieved the top performance experimentally among reported MOFs,in good agreement with the prediction. 展开更多
关键词 Metal-organic frameworks High-throughput screening Machine learning Explainable model CO_(2)cycloaddition
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High-throughput screening and evaluation of double-linker metal–organic frameworks for CO_(2)/H_(2)adsorption and separation
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作者 Ji-Long Huang Xiu-Ying Liu +2 位作者 Hao Chen Xiao-Dong Li Jing-Xin Yu 《Chinese Physics B》 2025年第2期408-417,共10页
The capture of CO_(2)from CO_(2)/H_(2)gas mixtures in syngas is a crucial issue for hydrogen production from steam methane reforming in industry,as the presence of CO_(2)directly affects the purity of H_(2).A combinat... The capture of CO_(2)from CO_(2)/H_(2)gas mixtures in syngas is a crucial issue for hydrogen production from steam methane reforming in industry,as the presence of CO_(2)directly affects the purity of H_(2).A combination of a high-throughput screening method and grand canonical Monte Carlo simulation was utilized to evaluate and screen 1725 metal–organic frameworks(MOFs)in detail as a means of determining their adsorption performance for CO_(2)/H_(2)gas mixtures.The adsorption and separation performance of double-linker MOFs was comprehensively evaluated using eight evaluation indicators,namely,the largest cavity diameter,accessible surface area,pore occupied accessible volume,porosity,adsorption selectivity,working capacity,adsorbent performance score and percent regeneration.Six optimal performance frameworks were screened to further study their single-component adsorption and binary competitive adsorption of CO_(2)/H_(2)respectively.The CO_(2)adsorption selectivity at different CO_(2)/H_(2)feed ratios was also evaluated,which indicated their excellent adsorption and separation performance.The microscopic adsorption mechanisms for CO_(2)and H_(2)at the molecular level were investigated by analyzing the radial distribution function and density distribution.This study may provide directional guidance and reference for subsequent experiments on the adsorption and separation of CO_(2)/H_(2). 展开更多
关键词 metal–organic framework ADSORPTION SEPARATION high-throughput screening grand canonical Monte Carlo simulation
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Consensus on rapid screening for prodromal Alzheimer's disease in China 被引量:3
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作者 Lin Huang Qinjie Li +10 位作者 Yao Lu Fengfeng Pan Liang Cui Ying Wang Ya Miao Tianlu Chen Yatian Li Jingnan Wu Xiaochun Chen Jianping Jia Qihao Guo 《General Psychiatry》 CSCD 2024年第1期1-16,共16页
Alzheimer's disease(AD)is a common cause of dementia,characterised by cerebral amyloid-βdeposition,pathological tau and neurodegeneration.The prodromal stage of AD(pAD)refers to patients with mild cognitive impai... Alzheimer's disease(AD)is a common cause of dementia,characterised by cerebral amyloid-βdeposition,pathological tau and neurodegeneration.The prodromal stage of AD(pAD)refers to patients with mild cognitive impairment(MCl)and evidence of AD's pathology.At this stage,disease-modifying interventions should be used to prevent the progression to dementia.Given the inherent heterogeneity of MCl,more specific biomarkers are needed to elucidate the underlying AD's pathology.Although the uses of cerebrospinal fluid and positron emission tomography are widely accepted methods for detecting AD's pathology,their clinical applications are limited by their high costs and invasiveness,particularly in low-income areas in China.Therefore,to improve the early detection of Alzheimer's disease(AD)pathology through cost-effective screening methods,a panel of 45neurologists,psychiatrists andgerontologistswas invited to establish a formal consensus on the screening of pAD in China.The supportive evidence and grades of recommendations are based on a systematic literature review andfocus group discussion.National meetings were held to allow participants to review,vote and provide their expert opinions to reach a consensus.A majority(two-thirds)decision was used for questions for which consensus could not be reached.Recommended screening methods are presented in this publication,including neuropsychological assessment,peripheral biomarkers and brain imaging.In addition,a general workflow for Screening pAD in China is established,which will help clinicians identify individuals at high risk and determine therapeutic targets. 展开更多
关键词 ALZHEIMER INCOME screenING
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Enhancing the Performance of Perovskite Light-Emitting Diodes via Synergistic Effect of Defect Passivation and Dielectric Screening 被引量:1
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作者 Xuanchi Yu Jia Guo +11 位作者 Yulin Mao Chengwei Shan Fengshou Tian Bingheng Meng Zhaojin Wang Tianqi Zhang Aung Ko Ko Kyaw Shuming Chen Xiaowei Sun Kai Wang Rui Chen Guichuan Xing 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第10期244-256,共13页
Metal halide perovskites,particularly the quasi-two-dimensional perovskite subclass,have exhibited considerable potential for next-generation electroluminescent materials for lighting and display.Nevertheless,the pres... Metal halide perovskites,particularly the quasi-two-dimensional perovskite subclass,have exhibited considerable potential for next-generation electroluminescent materials for lighting and display.Nevertheless,the presence of defects within these perovskites has a substantial influence on the emission efficiency and durability of the devices.In this study,we revealed a synergistic passivation mechanism on perovskite films by using a dual-functional compound of potassium bromide.The dual functional potassium bromide on the one hand can passivate the defects of halide vacancies with bromine anions and,on the other hand,can screen the charged defects at the grain boundaries with potassium cations.This approach effectively reduces the probability of carriers quenching resulting from charged defects capture and consequently enhances the radiative recombination efficiency of perovskite thin films,leading to a significant enhancement of photoluminescence quantum yield to near-unity values(95%).Meanwhile,the potassium bromide treatment promoted the growth of homogeneous and smooth film,facilitating the charge carrier injection in the devices.Consequently,the perovskite light-emitting diodes based on this strategy achieve a maximum external quantum efficiency of~21%and maximum luminance of~60,000 cd m^(-2).This work provides a deeper insight into the passivation mechanism of ionic compound additives in perovskite with the solution method. 展开更多
关键词 Synergistic passivation strategy Defects passivation Dielectric screening Perovskite light-emitting diodes
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Study on the clogging mechanism of punching screen in sand control by the punching structure parameters
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作者 Fu-Cheng Deng Fu-Lin Gui +5 位作者 Bai-Tao Fan Lei Wen Sheng-Hong Chen Ning Gong Yun-Chen Xiao Zhi-Hui Xu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期609-620,共12页
As an independent sand control unit or a common protective shell of a high-quality screen,the punching screen is the outermost sand retaining unit of the sand control pipe which is used in geothermal well or oil and g... As an independent sand control unit or a common protective shell of a high-quality screen,the punching screen is the outermost sand retaining unit of the sand control pipe which is used in geothermal well or oil and gas well.However,most screens only consider the influence of the internal sand retaining medium parameters in the sand control performance design while ignoring the influence of the plugging of the punching screen on the overall sand retaining performance of the screen.To explore the clogging mechanism of the punching screen,this paper established the clogging mechanism calculation model of a single punching screen sand control unit by using the computational fluid mechanics-discrete element method(CFD-DEM)combined method.According to the combined motion of particles and fluids,the influence of the internal flow state on particle motion and accumulation was analyzed.The results showed that(1)the clogging process of the punching sand control unit is divided into three stages:initial clogging,aggravation of clogging and stability of clogging.In the initial stage of blockage,coarse particles form a loose bridge structure,and blockage often occurs preferentially at the streamline gathering place below chamfering inside the sand control unit.In the stage of blockage intensification,the particle mass develops into a relatively complete sand bridge,which develops from both ends of the opening to the center of the opening.In the stable plugging stage,the sand deposits show a“fan shape”and form a“V-shaped”gully inside the punching slot element.(2)Under a certain reservoir particle-size distribution,The slit length and opening height have a large influence on the permeability and blockage rate,while the slit width size has little influence on the permeability and blockage rate.The microscopic clogging mechanism and its law of the punching screen prevention unit are proposed in this study,which has some field guidance significance for the design of punching screen and sand prevention selection. 展开更多
关键词 Punching screen Plugging CFD-DEM Size parameter Sand control
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From the perspective of experimental practice: High-throughput computational screening in photocatalysis
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作者 Yunxuan Zhao Junyu Gao +2 位作者 Xuanang Bian Han Tang Tierui Zhang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期1-6,共6页
Photocatalysis,a critical strategy for harvesting sunlight to address energy demand and environmental concerns,is underpinned by the discovery of high-performance photocatalysts,thereby how to design photocatalysts is... Photocatalysis,a critical strategy for harvesting sunlight to address energy demand and environmental concerns,is underpinned by the discovery of high-performance photocatalysts,thereby how to design photocatalysts is now generating widespread interest in boosting the conversion effi-ciency of solar energy.In the past decade,computational technologies and theoretical simulations have led to a major leap in the development of high-throughput computational screening strategies for novel high-efficiency photocatalysts.In this viewpoint,we started with introducing the challenges of photocatalysis from the view of experimental practice,especially the inefficiency of the traditional“trial and error”method.Sub-sequently,a cross-sectional comparison between experimental and high-throughput computational screening for photocatalysis is presented and discussed in detail.On the basis of the current experimental progress in photocatalysis,we also exemplified the various challenges associated with high-throughput computational screening strategies.Finally,we offered a preferred high-throughput computational screening procedure for pho-tocatalysts from an experimental practice perspective(model construction and screening,standardized experiments,assessment and revision),with the aim of a better correlation of high-throughput simulations and experimental practices,motivating to search for better descriptors. 展开更多
关键词 PHOTOCATALYSIS High-throughput computational screening PHOTOCATALYST Theoretical simulations Experiments
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Enhanced extracellular production of alpha-lactalbumin from Bacillus subtilis through signal peptide and promoter screening
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作者 Yuqi Zhu Pengdong Sun +6 位作者 Chunjian Li Yu Zhang Yu Wang Jingyuan Li Yanfeng Liu Jian Chen Yang Deng 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2310-2316,共7页
Alpha-lactalbumin(α-LA)is a major whey protein found in breast milk and plays a crucial role in the growth and development of infants.In this study,Bacillus subtilis RIK1285 harboring AprE signal peptide(SP)was selec... Alpha-lactalbumin(α-LA)is a major whey protein found in breast milk and plays a crucial role in the growth and development of infants.In this study,Bacillus subtilis RIK1285 harboring AprE signal peptide(SP)was selected as the original strain for the production ofα-LA.It was found thatα-LA was identified in the pellet after ultrasonic disruption and centrifugation instead of in the fermentation supernatant.The original strain most likely only producedα-LA intracellular,but not extracellular.To improve the expression and secretion ofα-LA in RIK1285,a library of 173 homologous SPs from the B.subtilis 168 genome was fused with target LALBA gene in the pBE-S vector and expressed extracellularly in RIK1285.SP YjcN was determined to be the best signal peptide.Bands in supernatant were observed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and purified by nickel column to calculate the highest yield signal peptide.In addition,different promoters(P_(aprE),P_(43),and P_(glv))were compared and applied.The results indicated that the strain RIK1285-pBE-P_(glv)-YjcN-LALBA had the highestα-LA yield,reaching 122.04μg/mL.This study demonstrates successful expression and secretion of humanα-LA in B.subtilis and establishes a foundation for simulating breast milk for infant formulas and developing bioengineered milk. 展开更多
关键词 Bacillus subtilis ALPHA-LACTALBUMIN Bioengineering milk Signal peptide Promoter screening
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Virtual screening and directional preparation of xanthine oxidase inhibitory peptides derived from hemp seed protein
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作者 Xiaoni Huang Jiajun Liao +2 位作者 Ping Shi Xiaodong Pei Chenghua Wang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第6期3652-3660,共9页
The traditional nutritional and medical hemp(Cannabis sativa L.)seed protein were explored for the discovery and directional preparation of new xanthine oxidase inhibitory(XOI)peptides by structure-based virtual scree... The traditional nutritional and medical hemp(Cannabis sativa L.)seed protein were explored for the discovery and directional preparation of new xanthine oxidase inhibitory(XOI)peptides by structure-based virtual screening,compound synthesis,in vitro bioassay and proteolysis.Six subtypes of hemp seed edestin and albumin were in silico hydrolyzed by 29 proteases,and 192 encrypted bioactive peptides were screened out.Six peptides showed to be XOI peptides,of which four(about 67%)were released by elastase hydrolysis.The peptide DDNPRRFY displayed the highest XOI activity(IC50=(2.10±0.06)mg/mL),acting as a mixed inhibitor.The pancreatic elastase directionally prepared XOI hemp seed protein hydrolysates,from which 6 high-abundance XOI peptides encrypted 3 virtually-screened ones including the DDNPRRFY.The novel outstanding hemp seed protein-derived XOI peptides and their virtual screening and directed preparation methods provide a promising and applicable approach to conveniently and efficiently explore food-derived bioactive peptides. 展开更多
关键词 Hemp seed protein Anti-gout Bioactive peptide Virtual screening PROTEOLYSIS
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Viscoacoustic generalized screen propagator in constant-Q model
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作者 Zhong-Kui Dai Jia-Chun You +1 位作者 Xing-Guo Huang Wei Liu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2356-2369,共14页
When seismic waves propagate through the geological formation,there is a significant loss of energy and a decrease in imaging resolution,because of the viscoacoustic properties of subsurface medium.This profoundly imp... When seismic waves propagate through the geological formation,there is a significant loss of energy and a decrease in imaging resolution,because of the viscoacoustic properties of subsurface medium.This profoundly impacts seismic wavefield propagation,imaging and interpretation.To accurately image the true structure of subsurface medium,the consensus among geophysicists is to no longer treat subsurface medium as ideal homogeneous medium,but rather to incorporate the viscoacoustic properties of subsurface medium.Based on the generalized screen propagator using conventional acoustic wave equation(acoustic GSP),our developed method introduces viscoacoustic compensation strategy,and derives a one-way wave generalized screen propagator based on time-fractional viscoacoustic wave equation(viscoacoustic GSP).In numerical experiments,we conducted tests on two-dimensional multi-layer model and the Marmousi model.When comparing with the acoustic GSP using the acoustic data,we found that the imaging results of the viscoacoustic GSP using the viscoacoustic data showed a significant attenuation compensation effect,and achieved imaging results for both algorithms were essentially consistent.However,the imaging results of acoustic GSP using viscoacoustic data showed significant attenuation effects,especially for deep subsurface imaging.This indicates that we have proposed an effective method to compensate the attenuated seismic wavefield.Our application on a set of real seismic data demonstrated that the imaging performance of our proposed method in local areas surpassed that of the conventional acoustic GSP.This suggests that our proposed method holds practical value and can more accurately image real subsurface structures while enhancing imaging resolution compared with the conventional acoustic GSP.Finally,with respect to computational efficiency,we gathered statistics on running time to compare our proposed method with conventional Q-RTM,and it is evident that our method exhibits higher computational efficiency.In summary,our proposed viscoacoustic GSP method takes into account the true properties of the medium,still achieves migration results comparable to conventional acoustic GSP. 展开更多
关键词 One-way wave equation Viscoacoustic wave equation Generalized screen propagator Attenuation and dispersion effects
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Accelerating the design of catalysts for CO_(2)electroreduction to HCOOH:A data-driven DFT-ML screening of dual atom catalysts
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作者 Huiwen Zhu Zeyu Guo +6 位作者 Dawei Lan Shuai Liu Min Liu Jianwen Zhang Xiang Luo Jiahui Yu Tao Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第12期627-635,共9页
Dual-atom catalysts(DACs)have emerged as potential catalysts for effective electroreduction of CO_(2)due to their high atom utilization efficiency and multiple active sites.However,the screening of DACs remains a chal... Dual-atom catalysts(DACs)have emerged as potential catalysts for effective electroreduction of CO_(2)due to their high atom utilization efficiency and multiple active sites.However,the screening of DACs remains a challenge due to the large number of possible combinations,making exhaustive experimental or computational screening a daunting task.In this study,a density functional theory(DFT)-based machine learning(ML)-accelerated(DFT-ML)hybrid approach was developed to test a set of 406 dual transition metal catalysts on N-doped graphene(NG)for the electroreduction of CO_(2)to HCOOH.The results showed that the ML algorithms can successfully capture the relationship between the descriptors of the DACs(inputs)and the limiting potential for HCOOH generation(output).Of the four ML algorithms studied in this work,the feedforward neural network model achieved the highest prediction accuracy(the highest correlation coefficient(R^(2))of 0.960 and the lowest root mean square error(RMSE)of 0.319 eV on the test set)and the predicted results were verified by DFT calculations with an average absolute error of 0.14 eV.The DFT-ML approach identified Co-Co-NG and Ir-Fe-NG as the most active and stable electrocatalysts for the electrochemical reduction of CO_(2)to HCOOH.The DFT-ML hybrid approach exhibits exceptional prediction accuracy while enabling a significant reduction in screening time by an impressive 64%compared to conventional DFT-only calculations.These results demonstrate the immense potential of using ML methods to accelerate the screening and rational design of efficient catalysts for various energy and environmental applications. 展开更多
关键词 CO_(2)electroreduction reaction Dual atom catalysts Rapid screening Density functional theory Machine learning
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Censored Composite Conditional Quantile Screening for High-Dimensional Survival Data
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作者 LIU Wei LI Yingqiu 《应用概率统计》 CSCD 北大核心 2024年第5期783-799,共17页
In this paper,we introduce the censored composite conditional quantile coefficient(cC-CQC)to rank the relative importance of each predictor in high-dimensional censored regression.The cCCQC takes advantage of all usef... In this paper,we introduce the censored composite conditional quantile coefficient(cC-CQC)to rank the relative importance of each predictor in high-dimensional censored regression.The cCCQC takes advantage of all useful information across quantiles and can detect nonlinear effects including interactions and heterogeneity,effectively.Furthermore,the proposed screening method based on cCCQC is robust to the existence of outliers and enjoys the sure screening property.Simulation results demonstrate that the proposed method performs competitively on survival datasets of high-dimensional predictors,particularly when the variables are highly correlated. 展开更多
关键词 high-dimensional survival data censored composite conditional quantile coefficient sure screening property rank consistency property
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陕西省月用水量预测方法研究 被引量:1
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作者 陈星 沈紫菡 +2 位作者 许钦 刘睿佳 蔡晶 《水利水电科技进展》 北大核心 2025年第1期73-78,共6页
基于国家水资源管理信息系统的月用水量数据分析,选用ARIMA模型、BP神经网络模型以及经过遗传算法(GA)优化的BP神经网络模型(GA-BP神经网络模型)进行月用水量模拟。在构建BP神经网络模型过程中,通过多源社会经济数据的整合与分析,采用... 基于国家水资源管理信息系统的月用水量数据分析,选用ARIMA模型、BP神经网络模型以及经过遗传算法(GA)优化的BP神经网络模型(GA-BP神经网络模型)进行月用水量模拟。在构建BP神经网络模型过程中,通过多源社会经济数据的整合与分析,采用平均影响值算法(MIV)和皮尔逊相关系数联合方法筛选月用水量的关键影响因子。研究结果表明,三种模型在陕西省月用水量预测中均表现出较高的精度,其中GA-BP神经网络模型的预测精度最高。为进一步验证影响因子对模拟结果的影响,采用不同方法筛选影响因子作为GA-BP神经网络模型的输入,模拟结果表明,MIV和皮尔逊相关系数联合方法提高了影响因子的选取精度,能够有效提升GA-BP神经网络模型的模拟性能。 展开更多
关键词 月用水量预测 ARIMA模型 遗传算法 神经网络模型 因子筛选 陕西省
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畜禽粪便发酵生产有机肥菌种筛选试验研究
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作者 李元新 成伟伟 +3 位作者 杨军祥 赵子惠 郭海龙 杨明 《中国饲料》 北大核心 2025年第5期58-62,共5页
为筛选出畜禽粪便发酵有机肥的复合微生物菌剂,试验选取枯草芽孢杆菌、地衣芽孢杆菌、贝莱斯芽孢杆菌、短小芽孢杆菌、植物乳杆菌、绿色木霉和米曲霉,按7%分别接种在牛粪、猪粪、鸡粪上,以发酵温度和总氮含量作为观测指标,进行单菌种发... 为筛选出畜禽粪便发酵有机肥的复合微生物菌剂,试验选取枯草芽孢杆菌、地衣芽孢杆菌、贝莱斯芽孢杆菌、短小芽孢杆菌、植物乳杆菌、绿色木霉和米曲霉,按7%分别接种在牛粪、猪粪、鸡粪上,以发酵温度和总氮含量作为观测指标,进行单菌种发酵试验。结果显示:温度在发酵后3~13 d上升幅度较大,其中鸡粪升温最快,猪粪次之,牛粪最慢,15~19 d温度变化趋于平缓。总体来看,贝莱斯芽孢杆菌、短小芽孢杆菌、绿色木霉发酵温度相对较高。从发酵后总氮含量可以看出,鸡粪和猪粪的总氮含量高于牛粪,7株菌分别发酵牛粪、猪粪、鸡粪后总氮含量高低的顺序大体趋势一致,短小芽孢杆菌和贝莱斯芽孢杆菌在三种粪便发酵中总氮含量均较高。绿色木霉在牛粪和鸡粪发酵中总氮含量由高到低均排第三,在猪粪上排第四。综合发酵温度和总氮含量可筛选出相互间无拮抗作用的贝莱斯芽孢杆菌、短小芽孢杆菌、绿色木霉作为复合微生物菌剂的菌种。 展开更多
关键词 畜禽粪便 发酵 有机肥 菌种 筛选
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干旱胁迫对旱地冬小麦产量及其抗旱相关基因表达的影响
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作者 杨虓 陈德来 +3 位作者 刘自成 李静 施万喜 孟建军 《干旱地区农业研究》 北大核心 2025年第1期69-75,共7页
为研究陇东旱地育成冬小麦品系的抗旱性与抗旱功能基因的关系,以6个旱地冬小麦新品系为试验材料,于2021—2022年、2022—2023年2个生长季在陇东学院西峰旱作农业试验站设置雨养无灌溉(CK)、旱棚防雨(干旱胁迫)和调控灌溉3个水分处理,测... 为研究陇东旱地育成冬小麦品系的抗旱性与抗旱功能基因的关系,以6个旱地冬小麦新品系为试验材料,于2021—2022年、2022—2023年2个生长季在陇东学院西峰旱作农业试验站设置雨养无灌溉(CK)、旱棚防雨(干旱胁迫)和调控灌溉3个水分处理,测定各品系冬小麦产量,评价其抗旱性,并分析了抗旱相关功能基因的相对表达量。结果表明,在水分胁迫和供水充足(含水量为70%田间持水量)情况下,6个小麦品系产量差值变化不一致,品系C(‘1576-2-0-2’)和品系D(‘15119-1-0-2’)两年试验结果的差值均最小,其余4个品系差值均超过平均差值。由雨养无灌溉试验结果可知,2022年为大旱年份,品系C、D的产量在6个供试品系中分别位居第1和第3,抗旱系数分别为0.89和1.02;2023年为相对丰水年,品系C、D的抗旱系数分别为0.77和1.12,说明这两个品系对气候异常不敏感,抗旱性良好。通过荧光定量PCR技术分析6个小麦品系在灌浆期干旱胁迫下旗叶中的相对表达量,结果显示TaCRT-D基因在6个品系中的表达水平最高,Wdreb2、XTH-7A、WIip19、TaCRT-D在品系C、D中的表达量高于其他品系。田间试验结果与PEG-6000高渗溶液模拟发芽期和苗期干旱胁迫的鉴定结果相一致,表明6个品系中‘1576-2-0-2’和‘15119-1-0-2’品系抗旱性强,且干旱胁迫下灌浆期旗叶中抗旱功能基因TaCRT-D的表达量可以作为冬小麦早期世代抗旱选择参考指标。 展开更多
关键词 旱地冬小麦 早期世代 干旱胁迫 抗旱基因 育种筛选
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泵房流道内波浪的影响因素和极值特性分析
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作者 郭永鑫 周春灌 +3 位作者 杨若冰 郭新蕾 付辉 王琪 《中国水利水电科学研究院学报(中英文)》 北大核心 2025年第1期10-18,共9页
滨海电厂泵房流道内波浪幅值的控制对保证工程建设的经济性和机组运行的稳定性具有重要意义。针对现有规范中泵房波浪控制标准无法溯源问题,本文开展了典型鼓形滤网泵房流道内波浪传播的大比尺物理模型试验,观测了流道内窄缝振荡、聚波... 滨海电厂泵房流道内波浪幅值的控制对保证工程建设的经济性和机组运行的稳定性具有重要意义。针对现有规范中泵房波浪控制标准无法溯源问题,本文开展了典型鼓形滤网泵房流道内波浪传播的大比尺物理模型试验,观测了流道内窄缝振荡、聚波和共振等特殊波浪现象,分析了不同因素对波况的影响和波高的极值特性,结果表明:流道内入射波高越大,胸墙相对淹没深度越小,透射波能越大,波动幅度也越大;吸水池波高总体随水深增大而减小,随周期(或波长)呈先增大后减小的非线性变化,当吸水池固有的波浪传播“回路”长度与入射波长相近时出现波高极大值。研究给出的流道内波浪传播规律和吸水池波浪“回路”长度计算方法可为滨海泵站工程的设计提供参考。 展开更多
关键词 泵房流道 鼓形旋转滤网 不规则波 吸水池 波浪共振
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ARTP诱变及高通量筛选选育米尔贝霉素高产菌株
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作者 张莉 米贯东 +4 位作者 戴梦 谢新宇 安兰兰 马婕 任风芝 《中国兽药杂志》 2025年第3期25-33,共9页
为选育米尔贝霉素(milbemycin)优良菌株,提高发酵产量,以吸水链霉菌(Streptomyces hygroscopicus)MB230906作为出发菌株,通过常压室温等离子体(ARTP),结合自身代谢产物抗性,以及高通量筛选技术,获得了1株遗传性状稳定的高产突变菌株AM24... 为选育米尔贝霉素(milbemycin)优良菌株,提高发酵产量,以吸水链霉菌(Streptomyces hygroscopicus)MB230906作为出发菌株,通过常压室温等离子体(ARTP),结合自身代谢产物抗性,以及高通量筛选技术,获得了1株遗传性状稳定的高产突变菌株AM2405-228,50 L罐发酵产量平均达到3494μg/mL,较出发菌株提升28.31%,A3∶A4达到了1∶3.98。结果表明,运用ARTP诱变结合抗性和高通量筛选,可以高效、快速获得发酵产量显著提高的米尔贝霉素突变株,为进一步推进米尔贝霉素的工业化生产奠定坚实的研究基础。 展开更多
关键词 米尔贝霉素 吸水链霉菌 ARTP 高通量筛选
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一株高产四甲基吡嗪细菌的筛选、鉴定及发酵研究
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作者 张杰 吴宏萍 +3 位作者 代森 潘天全 李娜 郝标 《酿酒》 2025年第2期94-98,共5页
四甲基吡嗪是白酒中重要的风味物质之一,该研究从金种子馥合香堆积粮醅中筛选出4株产四甲基吡嗪芽孢菌株,结合气相色谱-质谱联用仪对挥发性成分进行定量分析,确定一株高产四甲基吡嗪菌株DQ-5,16S rDNA测序该菌株为枯草芽孢杆菌Bacillus ... 四甲基吡嗪是白酒中重要的风味物质之一,该研究从金种子馥合香堆积粮醅中筛选出4株产四甲基吡嗪芽孢菌株,结合气相色谱-质谱联用仪对挥发性成分进行定量分析,确定一株高产四甲基吡嗪菌株DQ-5,16S rDNA测序该菌株为枯草芽孢杆菌Bacillus subtilis。对菌株DQ-5进行发酵试验测试,结果表明两个试验组均检测出四甲基吡嗪,其中LB5培养基中2,3,5,6-四甲基吡嗪含量为16μg/L,THY5培养基中2,3,5,6-四甲基吡嗪含量为52μg/L。 展开更多
关键词 馥合香粮醅 筛选分离 四甲基吡嗪
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会宁半干旱区全生物降解地膜覆盖栽培下玉米品种筛选试验
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作者 周刚 李尚中 +4 位作者 樊廷录 赵刚 张建军 党翼 王磊 《寒旱农业科学》 2025年第1期28-33,共6页
研究筛选会宁半干旱地区抗旱高产优质玉米品种,为促进会宁半干旱地区全生物降解地膜替代普通地膜种植方式的进一步转变提供科学依据。以引进的11个抗旱玉米品种为试验材料,利用全生物降解黑色地膜及全膜双垄覆盖沟播技术,测定和分析玉... 研究筛选会宁半干旱地区抗旱高产优质玉米品种,为促进会宁半干旱地区全生物降解地膜替代普通地膜种植方式的进一步转变提供科学依据。以引进的11个抗旱玉米品种为试验材料,利用全生物降解黑色地膜及全膜双垄覆盖沟播技术,测定和分析玉米的生育期、农艺性状、产量、SPAD值及品质指标。结果表明,在种植密度为6万株/hm^(2)时,先玉1483折合产量最高,为9584.1 kg/hm^(2);MC703、迪卡C1563折合产量较高,分别为9147.8、8987.2 kg/hm^(2)。先玉1483、MC703、迪卡C1563生育期均为127 d,灌浆时期叶片SPAD值分别为55.7、56.5、52.3,后期的光合能力较强,且综合籽粒营养品质较好。以上3个玉米品种可作为会宁半干旱区使用全生物降解地膜进行全膜双垄沟播种植模式下的示范推广品种。 展开更多
关键词 玉米 品种 全生物降解地膜 筛选试验 会宁半干旱区
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特殊润湿性材料分离乳液的影响因素
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作者 吴云 《石油化工》 北大核心 2025年第1期55-61,共7页
自主研发了特殊润湿性不锈钢筛网,分别考察了温度、过滤压力、pH、水油比、乳化剂用量等因素对特殊润湿性材料分离油水乳液的影响。实验结果表明,较低的温度对单层和双层筛网分离油包水(W/O)型和水包油(O/W)型乳液均有利;较低的过滤压力... 自主研发了特殊润湿性不锈钢筛网,分别考察了温度、过滤压力、pH、水油比、乳化剂用量等因素对特殊润湿性材料分离油水乳液的影响。实验结果表明,较低的温度对单层和双层筛网分离油包水(W/O)型和水包油(O/W)型乳液均有利;较低的过滤压力对W/O型乳液有利,过高的压力会直接影响筛网的疏水阻隔作用,双层筛网的分离机理决定了低过滤压力下分离无法进行,而更高的压力对双层筛网分离O/W型乳液更有利;低pH对两种类型的乳液分离均有利,随着pH的增大,分离效果下降;随着W/O型乳液含水率增大,单层筛网的分离效果不断下降,水在疏水筛网表面的占据会导致油的通过阻力迅速增大,甚至无法通过,而随着O/W型乳液含油率增大,双层筛网的分离效果呈增大趋势,这与水量下降导致的油水二次混合几率减少有关;乳化剂用量增加导致乳液稳定性增强,对两种类型乳液的分离均不利。 展开更多
关键词 油水分离 特殊润湿性 筛网 乳液 影响因素
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一株木质素降解真菌菌株的筛选、鉴定及培养基组分优化
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作者 章林 王晓娜 +3 位作者 周勇 杨光 贾晓丽 孙思琦 《吉林林业科技》 2025年第1期1-8,共8页
为探索木质素降解真菌对森林地被可燃物的降解效果,以阔叶红松林、山杨-白桦混交林、落叶松-白桦混交林、红皮云杉林地被可燃物为降解菌种来源与降解试验样品,对经降解后的可燃物质量损失率与木质素降解率进行了分析。筛选出1株对地被... 为探索木质素降解真菌对森林地被可燃物的降解效果,以阔叶红松林、山杨-白桦混交林、落叶松-白桦混交林、红皮云杉林地被可燃物为降解菌种来源与降解试验样品,对经降解后的可燃物质量损失率与木质素降解率进行了分析。筛选出1株对地被可燃物中木质素有较好降解能力的菌株,经鉴定为Phlebiopsis pilatii。该菌株最先表现出较强的木质素降解能力,其处理后10 d山杨-白桦混交林和红皮云杉林地被可燃物中木质素降解率分别为19.69%和16.01%,其处理后60 d落叶松-白桦混交林、红皮云杉林地被可燃物质量损失率为23.00%和22.00%。蔗糖、大豆粉和氯化钙分别为该菌株的最适产酶碳源、氮源和无机盐,确定优化后的发酵培养基配方,蔗糖为10.0 g·L^(-1),大豆粉为20.0 g·L^(-1),氯化钙为3.0 g·L^(-1),吐温-80为0.5 g·L^(-1)。 展开更多
关键词 木质素降解真菌 菌株筛选 森林地被可燃物 培养基优化
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