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Studies on Optical Properties of Si220 Nanoclusters viaTime-dependent Density Functional Theory Calculations

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Chemical Research in Chinese Universities 2016年第6期32卷 1028-1033页

作者： yang wenhua LU Wencai XUE Xuyan ZANG Qingjun WANG Caizhuang Institute of Theoretical Chemistry Jilin University Changchun 130021 P. R. China Laboratory of Fiber Materials and Modern Textile Growing Base for State Key Laboratory College of Physics Qingdao University Qingdao 266071 P. R. China Ames Laboratory-US DOE and Department of Physics and Astronomy Iowa State University Ames LA 50011 USA

The optical properties of bare and hydrogen passivated Si220 nanoclusters（NCs） in four typical motifs（i.e.,bulk-like, onion-like, bucky-diamond and icosahedral motifs） were studied via time-dependent density functionaltheory（TD-DFT） calculations. The calculation results show that there is a significant blue shift in the optical absorp-tion spectra when the Si NCs are passivated with hydrogen. A strong absorption peak in the visible light region ap-years for the hydrogenated bulk-like, onion-like and bucky-diamond Si NCs.

关键词： Si220 nanocluster Optical property Time-dependent density functional theory(TD-DFT)

Cloning,expression and improvement of catalytic activity of alginate lyase by site-directed mutation

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Systems Microbiology and Biomanufacturing 2022年第3期2卷 555-567页

作者： Yu Lu Jianli Zhou Qiuya Gu wenhua yang Liu yang Xiaobin Yu The Key Laboratory of Industrial Biotechnology Ministry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxi 214122China

Alginate lyase mainly produces active alginate oligosaccharides(AOS)by degrading alginate viaβ-elimination *** this study,the Pseudoalteromonas ***6B alginate lyase-encoding gene alg6B-7 from polysaccharide lyase(PL)-7 family was successfully cloned,sequenced,expressed in Escherichia *** on rational design and amino acid sequence alignment of the alginate lyase from various sources,four positive mutants were *** specific enzyme activities of four mutants I62A,A99K,V132S,and L157T were 38.84%,42.85%,75.8%and 51.83%higher than that of the wild enzyme,*** K_(cat)/K_(m) values of the four mutants were both increased,and the catalytic efficiency of V132S was 1.92-fold higher than that of the wild enzyme,*** rational design that was employed in this study achieved the dramatic improvement of catalytic activity,which may provide the application potential in industrial production.

关键词： Alginate lyase Rational design Active center Site-directed mutation Catalytic efficiency

Constitutive Relationship and Hot Processing Maps of Mg-Gd-Y-Nb-Zr Alloy

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Journal of Materials Science & Technology 2017年第7期33卷 637-644页

作者： Zhaohui Zhou Qichao Fan Zhihui Xia Aiguo Hao wenhua yang Wei Ji Haiqiao Cao Institute of Machinery Manufacturing Technology Chinese Academy of Engineering Physics Mianyang 621900 China

The hot working behavior of Mg-Gd-Y-Nb-Zr alloy was investigated using constitutive model and hot processing maps in this work. Isothermal compression tests were conducted with temperature and strain rate range of 703-773 K and 0.01-5 s^（-1）, respectively. Improved Arrhenius-type equation incorporated with strain compensations was used to predict flow behavior of the alloy, and the predictability was evaluated using correlation coefficient, root mean square error and absolute relative error. Processing maps were constructed at different strains for Mg-Gd-Y-Nb-Zr alloy based on dynamic materials *** processing maps are divided into three domains and the corresponding microstructure evolutions are referred to the forming of straight grain boundaries, twinning, dynamic recrystallization and grain growth. Instability occurred mainly at the strain rate range of 0.3s^（-1）-0.5s^（-1）. The optimum processing domain is mainly at the temperature range of 703-765 K with the strain rate range of 0.01-0.1 s^（-1）.

关键词： Magnesium alloy Recrystallization Constitutive model Processing maps Hot deformation

Compound Zhebei granules combined with chemotherapy for the treatment of refractory acute leukemia: a randomized clinical trial

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Journal of Traditional Chinese Medicine 2016年第5期36卷 606-612页

作者： Hou Li yang Shulian yang wenhua Zhou Yuhong Liu Feng yang Hongyong Sun Weizheng Li Dongyun Xu Yamei Chen Xinyi Department of Oncology and Hematology Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine Department of Hematology Langfang Chinese Medicine Hospital Affiliated to Hebei Medical University Department of Hematology First Affiliated Hospital of Tianjin University of Traditional Chinese Medicine Department of Hematology Chinese Medicine Hospital of Zhejiang Province Department of Hematology Xiyuan Hospital Affiliated to China Academy of Chinese Medical Sciences Department of Hematology First Affiliated Hospital of Guangzhou University of Chinese Medicine Department of Hematology First Affiliated Hospital of Heilongjiang University of Chinese Medicine

OBJECTIVE: To observe the effect of compound Zhebei granules(CZBG) with chemotherapy in the treatment of refractory acute ***: In this multicenter, double-blind, placebo-controlled clinical trial, we used a central(online) randomization system to assign 235 patients to two treatment groups. A total of 118 patients received chemotherapy combined with CZBG(4 g,twice daily) and 117 patients received chemotherapy plus placebo. The clinical efficacy was evaluated at the end of one chemotherapeutic ***: In the full analysis set, in which deaths due to disease progression were regarded as inefficacy, the rates of complete remission(CR) and partial remission(CR + PR) were 32.35% and 50.00%,respectively, for the chemotherapy combined with CZBG group, and 23.08% and 35.58%, respectively,for the chemotherapy plus placebo group. There was a statistically significant difference between the two groups according to a ysis set(PPχ2test(P < 0.05). In the per protocol analS), the CR(33.67%),CR+PR(52.04%) response rates for the chemotherapy plus CZBG group were significantly different from the response rates of the control group(CR:24.24% and CR+PR: 37.37%), respectively(P < 0.05).CONCLUSION: CZBG plus chemotherapy can improve the clinical remission rate of refractory acute leukemia after one just one therapeutic cycle.

关键词： Refractory acute leukemia Zhebei granules Chemotherapy remission rate Randomized clinical trial

Morphological and molecular evidence for natural hybridization between Sorbus pohuashanensis and S. discolor (Rosaceae)

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Journal of Forestry Research 2024年第4期35卷 189-201页

作者： Yuxia Wu Xuedan Yu Wei Tang wenhua yang Qidi Fu Yongqi Zheng Chuanhong Zhang State Key Laboratory of Tree Genetics and Breeding Research Institute of ForestryChinese Academy of ForestryBeijing 100091People’s Republic of China Beijing Waiyan Online Digital Technology Co. LtdBeijing 100081People’s Republic of China Huabanlv Nature Enlightenment Education Technology Co. LtdBeijing 100010People’s Republic of China

In overlapping distribution areas of Sorbus pohuashanensis and *** in North China(Mount Tuoliang,Mount Xiling and Mount Baihua),Sorbus indi-viduals were found with pink fruit,which have never been recorded for the flora of *** morphological characters combined with four chloroplast DNA markers and internal transcribed spacer(ITS)were used to analyze the origin of the Sorbus individuals with pink fruits and their relationship to *** and ***,SDA and one-way(taxon)ANOVA of morphological characters provided convincing evidence of the hybrid ori-gin of Sorbus individuals with pink fruits based on a novel morphological character and many intermediate *** analysis based on four cpDNA markers showed that either *** or *** were maternal parents of Sorbus individuals with pink ***-ence of the position of Sorbus individuals with pink fruits between cpDNA and ITS in cluster trees supported by DNA sequence comparative analysis,implying former hybridiza-tion events between *** and ***-tiple hybridization events between *** and *** might have contributed to the generation of Sorbus individuals with pink *** study has provided insights into hybridization between species of the same genus in sympatric areas,which is of great significance for the study of interspecific hybridization.

关键词： Hybridization ITS Chloroplast DNA Morphological characters Sorbus

Patterned growth ofβ-Ga_(2)O_(3) thin films for solar-blind deep-ultraviolet photodetectors array and optical imaging application

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Journal of Materials Science & Technology 2021年第13期72卷 189-196页

作者： Chao Xie Xingtong Lu Yi Liang Huahan Chen Li Wang Chunyan Wu Di Wu wenhua yang Linbao Luo School of Electronic Science and Applied Physics Hefei University of TechnologyHefei230009China School of Physics and Microelectronics Zhengzhou UniversityZhengzhou450052China

Solar-blind deep-ultraviolet(DUV)photodetectors based on Ga_(2)O_(3)have attracted great attention due to their potential applications for many military and civil ***,the development of device integration for optoelectronic system applications remains a huge ***,we report a facile method for patterned-growth of high-qualityβ-Ga_(2)O_(3)thin films,which are assembled into a photodetectors array comprising 8×8 device units.A representative detector exhibits outstanding photoresponse performance,in terms of an ultra-low dark current of 0.62 pA,a large Ilight/Idark ratio exceeding 10^(4),a high responsivity of 0.72 A W^(-1) and a decent specific detectivity of 4.18×10^(11)Jones,upon 265 nm DUV *** is more,the DUV/visible(250/400 nm)rejection ratio is as high as 10^(3) with a sharp response cut-off wave length at 280 *** optoelectronic analysis reveals that the photodetectors array has good uniformity and repeatability,endowing it the capability to serve as a reliable DUV light image sensor with a decent spatial *** results suggest that the proposed technique offers an effective avenue for patterned growth ofβ-Ga_(2)O_(3)thin films for multifunctional DUV optoelectronic applications.

关键词： Ultrawide-bandgap semiconductor Solar-blind Deep ultraviolet photodetection Patterned growth Image sensor

Epitaxial growth of ultrathin ZrO_2(111) films on Pt(111)

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Chinese Science Bulletin 2011年第6期56卷 502-507页

作者： GAO Yan ZHANG Liang PAN YongHe WANG GuoDong XU yang ZHANG wenhua ZHU JunFa National Synchrotron Radiation Laboratory University of Science and Technology of China Hefei 230029 China

Ordered epitaxial ZrO2 films were grown on Pt(111) and characterized by low energy electron diffraction (LEED), synchrotron radiation photoemission spectroscopy (SRPES) and X-ray photoelectron spectroscopy (XPS). The films were prepared by vapor deposition of zirconium in an O2 atmosphere followed by annealing under ultra high vacuum. At low coverages, the films grew as discontinuous two-dimentional islands with ordered structures. The size and structure of these islands were dependent on the coverage of ZrO2 films. At coverage 6 ML, a continuous ZrO2(111) film was formed with a (1×1) surface LEED pattern coexisting with a (2×2) pattern. These ordered thin ZrO2 films provide good model surfaces of bulk ZrO2 and can be used for further fundamental studies of the surface chemistry of ZrO2 using modern surface science techniques.

关键词：二氧化锆薄膜薄膜外延生长同步辐射光电子能谱超薄有序结构表面图案低能电子衍射化学基础研究

Investigation on environment monitoring system for a combination of hydroponics and aquaculture in greenhouse

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Information Processing in Agriculture 2022年第1期9卷 123-134页

作者： Shanhong Zhang Yu Guo Shuai Li Zhixin Ke Huajian Zhao Jinqi yang yang Wang Daoliang Li Liang Wang wenhua yang Zhili Zhang National Innovation Center for Digital Fishery China Agricultural UniversityBeijing 100083China College of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China Beijing Zhong Nong Tianlu Micro-nano Bubble Water Science and Technology Co. LtdChina

This work develops a distributed environmental monitoring system for the combination of hydroponics and aquaculture based on the internet of things technology,which mainly includes the information perception layer,the information transmission layer and the sys-tem *** system has employed multiple sensors terminal to real-time acqui-sition,including air and water temperatures,dissolved oxygen *** protocol is suitable for sending small data and the 4G was employed to collect data and send to the cloud *** is used to develop background applications,to access cloud platforms and local data *** on the collection and processing of environmental data and cloud service platform,the mobile application program client and remote login desktop have been *** has been implemented and tested in Tongzhou,Beijing for 3 months in *** results showed the proposed monitoring system stability for overall operation and accuracy data transmission,which can support the actual hydroponics and aquacul-ture production *** analysis of monitoring data collected from the devel-oped monitoring system,indoor air and water temperature have the obvious correlation with atmospheric pressure(0.7 and 0.9)and outdoor temperature(1.0 and 0.9),respectively.

关键词： Monitoring system Hydroponics Aquaculture Greenhouse Internet of things Greenhouse environment

Uncertainty quantification and reduction in metal additive manufacturing

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npj Computational Materials 2020年第1期6卷 214-223页

作者： Zhuo Wang Chen Jiang Pengwei Liu wenhua yang Ying Zhao Mark F.Horstemeyer Long-Qing Chen Zhen Hu Lei Chen Department of Mechanical Engineering University of Michigan-DearbornDearbornMI 48128USA Department of Industrial and Manufacturing Systems Engineering University of Michigan-DearbornDearbornMI 48128USA School of Mechanical Engineering Yanshan UniversityQinhuangdaoHebei 066004China Department of Mechanical Engineering Mississippi State UniversityStarkvilleMS 39762USA School of Engineering Liberty UniversityLynchburgVA 24515USA Department of Materials Science and Engineering The Pennsylvania State UniversityUniversity ParkPA 16802USA Michigan Institute for Data Science University of MichiganAnn ArborMI 48109USA

Uncertainty quantification(UQ)in metal additive manufacturing(AM)has attracted tremendous interest in order to dramatically improve product ***-based UQ,which relies on the validity of a computational model,has been widely explored as a potential substitute for the time-consuming and expensive UQ solely based on ***,its adoption in the practical AM process requires overcoming two main challenges:(1)the inaccurate knowledge of uncertainty sources and(2)the intrinsic uncertainty associated with the computational ***,we propose a data-driven framework to tackle these two challenges by combining high throughput physical/surrogate model simulations and the AM-Bench experimental data from the National Institute of Standards and Technology(NIST).We first construct a surrogate model,based on high throughput physical simulations,for predicting the three-dimensional(3D)melt pool geometry and its uncertainty with respect to AM parameters and uncertainty *** then employ a sequential Bayesian calibration method to perform experimental parameter calibration and model correction to significantly improve the validity of the 3D melt pool surrogate *** application of the calibrated melt pool model to UQ of the porosity level,an important quality factor,of AM parts,demonstrates its potential use in AM quality *** proposed UQ framework can be generally applicable to different AM processes,representing a significant advance toward physicsbased quality control of AM products.

关键词： additive consuming correction