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Purification and Characterization of Two Thermostable Glucoamylases Produced from Aspergillus niger B-30

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Chemical Research in Chinese Universities 2013年第5期29卷 917-923页

作者： liU Yang li Quan-shun ZHU Hong-liang meng zhao-li XIANG Hong-yu XIE Qiu-hong Key Laboratory for Molecular Enzymology and Engineering Ministry of Education National Engineering Laboratory for AIDS Vaccine School of Life Sciences Jilin University Changchun 130012 P. R. China Zibo Guoao Biotechnology Co. Ltd. Zibo 255400 P. R. China

Two thermostable glucoamylases were produced from Aspergillus niger B-30 by submerged fermentation. The two glueoamylases GAM-1 and GAM-2 were purified by ammonium sulfate precipitation, diethylaminoethyl- cellulose fast flow（DEAE FF） and Superdex G-75 gel filtration columns. The molecular weights of GAM-1 and GAM-2 were determined as 9.72x 104 and 7.83x104 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis （SDS-PAGE）, while the molecular weights of GAM-1 and GAM-2 were determined to be 8.05x 104 and 7.04x 104 by matrix assisted laser desorption ionizationtime-of-flight（MALDI-TOF） mass spectrometry, respectively. Both the enzymes were glycosylated, with 10.4% and 11.4% carbohydrate content, respectively. The optimal pH and tempera- ture were 4.0--4.6 and 70 ℃ for both. The two glucoamylases were maintained 100% relative activity after incuba- tion at 60 ℃ for 120 min. After the hydrolysis of starch for 120 min, glucose was the only product, confirming that the two enzymes were of high efficiency towards starch. The GAM-2 exhibited higher catalytic activity towards oli- gosaccharides such as maltose than GAM-1, and the kinetic analysis shows that the affinity of GAM-2 to starch was lower than that of GAM-1. The high thermostability and effectiveness make the two glucoamylases potentially attrac- tive for biotechnological application.

关键词： Glucoamylase Thermostability Kinetic analysis Glycosylation

内蒙古不同类型草原植物群落叶片氮、磷含量变化研究

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草地学报 2025年第2期33卷 465-471页

作者：徐龙超李邵宇白梅张峰张彬杨立山王文琼邢佳庆乌云嘎赵萌莉内蒙古农业大学草原与资源环境学院内蒙古呼和浩特010010 黄河海勃湾水利事业发展中心内蒙古乌海016000

内蒙古草原作为我国北方生态安全屏障,其植物叶片氮、磷含量变化对于理解生态系统响应环境变化至关重要。鉴于此,本研究以内蒙古草原为研究对象,通过样地调查和室内分析,系统分析了植物叶片氮、磷含量与气候因子、土壤理化性质以及根系... 详细信息

内蒙古草原作为我国北方生态安全屏障,其植物叶片氮、磷含量变化对于理解生态系统响应环境变化至关重要。鉴于此,本研究以内蒙古草原为研究对象,通过样地调查和室内分析,系统分析了植物叶片氮、磷含量与气候因子、土壤理化性质以及根系和土壤中氮、磷含量的关系。结果表明:(1)内蒙古草原叶片氮、磷元素浓度的平均值分别为14.08 mg·g^(-1)和1.28 mg·g^(-1)。(2)降水和温度与叶片氮、磷含量变化呈现出极显著的非线性关系(P<0.001);土壤含水量和pH值与叶片氮含量变化呈现出显著的线性关系(P<0.05),土壤容重、含水量和pH值与叶片磷含量变化呈现出显著的线性关系(P<0.05)。(3)结构方程模型结果表明,降水是影响叶片氮、磷含量的重要因子。研究表明,水分是内蒙古草原植物群落叶片氮、磷含量的主要影响因子,本研究结果可为内蒙古草原生态系统功能调节及生物多样性保护提供理论依据。

关键词：叶片氮叶片磷气候因子土壤理化性质内蒙古草原

Performance of AC-LGAD strip sensors designed for the DarkSHINE experiment

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Nuclear Science and Techniques 2024年第11期35卷 152-163页

作者： Kang liu meng-zhao li Jun-Hua Zhang Wei-Yi Sun Yun-Yun Fan Zhi-Jun liang Yu-Feng Wang Mei zhao Kun liu Tsung‑Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 201210China Key Laboratory for Particle Astrophysics and Cosmology(MOE) Shanghai Key Laboratory for Particle Physics and Cosmology(SKLPPC)Shanghai 200240China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Institute of Nuclear and Particle Physics School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China

The DarkSHINE experiment proposes a novel approach to single-electron-on-fixed-target exploration that focuses on the search for dark photons through their invisible decay into dark matter *** to this initiative is an advanced tracking detector designed to achieve exceptional sensitivity in the detection of light dark matter *** study evaluates the performance of several prototype AC-coupled low-gain avalanche diode(AC-LGAD)strip sensors specifically developed for the DarkSHINE tracking *** electrical properties of the sensors from two batches of wafers with different n^(+)doses are thoroughly *** and temporal resolutions are measured using an infrared laser *** spatial resolutions range from 6.5 to 8.2μm and from 8.8 to 12.3μm for the sensors from two distinct dose batches,each with a 100μm pitch ***,the sensors demonstrate time resolutions of 8.3 and 11.4 ps,underscoring the potential of AC-LGAD technology in enhancing the performance of the DarkSHINE tracking detector.

关键词： The DarkSHINE experiment Silicon-strip detector AC-LGAD sensor Spatial resolution Timing resolution

A Simplified Method to Calculate the Wet Bulb Globe Temperature(WBGT)

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湖南大学学报（自然科学版） 2009年第S1期36卷 40-44页

作者： ZHANG Lei,meng Qing-lin,zhao li-hua,ZHANG Yu-feng(State Key Laboratory of Subtropical Building Science,South China University of Technology,Guangzhou,Guangdong 510640,China) State Key Laboratory of Subtropical Building Science South China University of Technology Guangzhou 510640 China

Wet bulb globe temperature(WBGT)is a comprehensive index obtained mainly from three parameters:black globe temperature(Tg),wet bulb temperature(Tw),and dry bulb temperature(Ta).While in field observation and numerical simulation,black globe temperature and wet bulb temperature were not easy to obtain,so WBGT was difficult to measure and calculate *** order to solve this problem,air dry bulb temperature,wet bulb temperature,globe temperature,relative humidity,mean air velocity,solar radiation and wet bulb globe temperature were collected during the summer(July)in *** analysis and regression analysis were used to get a simplified method to calculate *** results showed that dry bulb temperature,relative humidity,solar radiation and WBGT were interrelated to some *** three parameters could be used in the simplified method to predict WBGT,and the linear correlation and precision of this model were *** addition,we used the measured data to verify the simplified method,and the results showed that the error of the calculated value and the measured value was all below 5%,which means the simplified calculating method is feasible and can be used in field observation and simulation research of urban thermal environment.

关键词： hot and humid regions urban thermal environment wet bulb globe temperature multivariate linear regression

Polydopamine-modified biochar supported polylactic acid and zero-valent iron affects the functional microbial community structure for 1,1,1-trichloroethane removal in simulated groundwater

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Chinese Chemical Letters 2025年第1期36卷 420-426页

作者： Haitao Yin liang meng li li Jiamu Xiao Longrui liang Nannan Huang Yansong Shi Angang zhao Jingwen Hou School of Environmental and Geographical Sciences Shanghai Normal UniversityShanghai 200234China Yangtze River Delta Urban Wetland Ecosystem National Field Scientific Observation and Research Station Shanghai 201722China Instrumental Analysis Center Shanghai Jiao Tong UniversityShanghai 200240China

In-situ enhanced bioreduction by functional materials is a cost-effective technology to remove chlorinated hydrocarbons in ***,a novel polydopamine(PDA)-modified biochar(BC)-based composite containing nanoscale zero-valent iron(n ZVI)and poly-l-lactic acid(PLLA)(PB-PDA-Fe)was synthesized to enhance the removal of 1,1,1-trichloroethane(1,1,1-TCA)in simulated groundwater with actual site *** impact on functional microbial community structure in system was also *** typical characterizations revealed uniform dispersion of PLA and n ZVI particles on the BC surface,being smoother after PDA *** composite exhibited a significantly higher performance on 1,1,1-TCA removal(82.38%,initial concentration 100 mg/L)than Fe-PDA and PB-PDA *** diversity and richness of the microbial community in the composite treatment consistently decreased during incubation due to a synergistic effect between PLLA-BC and n ***,Pedobacter,Sphaerochaeta,Shewanella,and Clostridium were identified as enriched genera by the composite through DNA-stable isotope probing(DNA-SIP),playing a crucial role in the bioreductive dechlorination *** the above results demonstrate that this novel composite selectively enhances the activity of microorganisms with extracellular respiration functions to efficiently dechlorinate 1,1,*** findings could contribute to understanding the responsive microbial community by carbon-iron composites and expedite the application of in-situ enhanced bioreduction for effective remediation of chlorinated hydrocarbon-contaminated groundwater.

关键词： Biochar-based composite Bioreductive dechlorination 1,1,1-TCA Extracellular respiration microorganisms Groundwater

Geometric-like imaginarity:Quantification and state conversion

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 13-22页

作者： meng-li Guo Bo li Shao-Ming Fei School of Science East China University of TechnologyNanchang 330006China School of Computer and Computing Science Hangzhou City University Hangzhou 310015China School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

From the perspective of resource-theoretic approach,this study explores the quantification of imaginary in quantum *** propose a well defined measure of imaginarity,the geometric-like measure of *** with the usual geometric imaginarity measure,this geometric-like measure of imaginarity exhibits smaller decay difference under quantum noisy channels and higher *** applications,we show that both the optimal probability of state transformations from a pure state to an arbitrary mixed state via real operations,and the maximal probability of stochastic-approximate state transformations from a pure state to an arbitrary mixed state via real operations with a given fidelity f,are given by the geometric-like measure of imaginarity.

关键词： quantum resource theory imaginarity geometric-like channels state transformations

A non-fluorinated liquid-like membrane with excellent anti-scaling performance for membrane distillation

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Chinese Chemical Letters 2025年第1期36卷 521-528页

作者： Jianwen zhao Shuai Wang Shanshan zhao liwei Chen Fangang meng Xuelin Tian State Key Laboratory of Optoelectronic Materials and Technologies School of Materials Science and EngineeringSun Yat-sen UniversityGuangzhou 510006China Key Laboratory for Polymeric Composite&Functional Materials of Ministry of Education Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable DevicesSun Yat-sen UniversityGuangzhou 510006China Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology School of Environmental Science and EngineeringSun Yat-sen UniversityGuangzhou 510006China

Membrane distillation(MD)has gained extensive attention for treating highly saline ***,membrane scaling during the MD process has hindered the rapid development of this *** approaches to mitigate scaling in membrane distillation focus primarily on achieving enhanced hydrophobicity and even superhydrophobicity via utilizing fluorinated fibrous membrane or introducing perfluorosilane *** the environmental hazards posed by fluorinated compounds,it is highly desirable to develop non-fluorinated membranes with enhanced anti-scaling properties for effective membrane *** this study,we present a non-fluorinated liquid-like MD membrane with exceptional anti-scaling *** membrane was facilely fabricated by grafting linear polydimethylsiloxane(LPDMS)onto a hydrophilic polyether sulfone(PES)membrane pre-coated with the intermediate layers of polydopamine and silica(denoted as LPDMS-PES).Remarkably,LPDMS-PES manifested a drastically improved scaling resistance in continuous MD tests than its perfluorinated counterpart,i.e.,1H,1H,2H,2H-perfluorooctyltrichlorosilane-modified PES membrane(PFOS-PES),in both heterogeneous nucleation-dominated and crystal deposition-dominated scaling processes,despite the latter having a smaller surface ***-PES demonstrated a reduction of crystal accumulation of approximately 85%for Na Cl and 73%for Ca SO_(4) in the heterogeneous nucleation-dominated scaling process compared to ***,in the crystal deposition-dominated scaling process LPDMS-PES exhibited a reduction of about 70%in scale *** results explicitly evidenced the great potential of the liquid-like membrane to minimize scaling in membrane distillation by inhibiting both scale nucleation and adhesion onto the *** believe the findings of this study have important implications for the design of high-performance MD membranes,particularly in the quest for environmentally susta

关键词： Surface modification liquid-like membranes Anti-scaling Non-fluorinated Direct contact membrane distillation

Ti^(3+)/Ti^(4+)and Co^(2+)/Co^(3+)redox couples in Ce-doped Co-Ce/TiO2 for enhancing photothermocatalytic toluene oxidation

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Journal of Environmental Sciences 2025年第3期149卷 164-176页

作者： Guanghui li Xiaolan li Xinhui Hao Qiang li meng Zhang Hongpeng Jia Xiamen Key Laboratory of Materials for Gaseous Pollutant Control Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China CAS Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

Cerium and cobalt loaded Co-Ce/TiO_(2)catalyst prepared by impregnation method was investigated for photothermal catalytic toluene *** on catalyst characterizations(XPS,EPR and H2-TPR),redox cycle between Co and TiO_(2)(Co^(2+)+Ti^(4+)↔Co^(3+)+Ti^(3+))results in the formation of Co^(3+),Ti^(3+)and oxygen vacancies,which play important roles in toluene catalytic oxidation *** introduction of Ce brings in the dual redox cycles(Co^(2+)+Ti^(4+)↔Co^(3+)+Ti^(3+),Co^(2+)+Ce4+↔Co^(3+)+Ce3+),further promoting the elevation of reaction sites *** full spectrum irradiation with light intensity of 580mW/cm^(2),Co-Ce/TiO_(2)catalyst achieved 96%of toluene conversion and 73%of CO_(2)yield,obviously higher than Co/P25 and Co/TiO_(2).Co-Ce/TiO_(2)efficiently maintains 10-hour stability test under water vapor conditions and exhibits better photothermal catalytic performance than counterparts under different wavelengths *** catalytic reaction displays improved activities compared with thermal catalysis,which is attributed to the promotional effect of light including photocatalysis and light activation of reactive oxygen species.

关键词： Photothermal catalysis Redox cycle Oxygen vacancy VOCs Titanium dioxide

Electro-functionalized 2D nitrogen-carbon nanosheets decorated with symbiotic cobalt single-atoms/clusters

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Journal of Energy Chemistry 2025年第2期101卷 385-391页

作者： Xinyan Zhou Sifan Qiao Zhenzhen zhao Meiqi liu Kexin Song Fuxi liu Nailin Yue Xiujuan li meng Zou Wei Zhang Key Laboratory of Automobile Materials MOE and School of Materials Science & Engineering and Electron Microscopy Center and International Center of Future Science and Jilin Provincial International Cooperation Key Laboratory of High-Efficiency Clean Energy Materials Jilin University Key Laboratory of Bionic Engineering Ministry of Education Jilin University

Two-dimensional（2D） materials loaded with single atoms and clusters are being set at the forefront of catalysis due to their distinctive geometric and electronic ***,the usually-complicated synthesis procedures impede in-depth clarification of their catalytic *** this end,herein we developed an efficient one-step dimension-reduction carbonization strategy,with which we successfully architected a highly-efficient catalyst for oxygen reduction reaction（ORR）,featured with symbiotic cobalt single atoms and clusters decorated in two-dimensional（2D） ultra-thin（3.5 nm thickness）nitrogen-carbon *** synergistic effects of the two components afford excellent oxygen reduction activity in alkaline media(E1/2=0.823 V ***) and thereof a high power density(146.61 mW cm-2) in an assembled Zn-air *** revealed by theoretical calculations,the cobalt clusters can regulate electrons surrounding those individual atoms and affect the adsorption of intermediate *** a consequence,the derived active sites of single cobalt atoms lead to a significant improvement of the ORR ***,our work may fuel interests to delicate architectu re of single atoms and clusters coexisting 2D support toward optimal electrocatalytic performance.

关键词： Carbon-Nitrogen Nanosheets Oxygen reduction reaction Single atoms and clusters Two-dimensional