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Effect of transient space-charge perturbation on carrier transport in high-resistance CdZnTe semiconductor

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Chinese Physics B 2019年第11期28卷 304-307页

作者： Yu guo gang-Qiang zha Ying-Rui Li Ting-Ting Tan Hao Zhu sen Wu MIIT Key Laboratory of Radiation Detection Materials and Devices State Key Laboratory of Solidification ProcessingSchool of Materials Science and EngineeringNorthwestern Polytechnical University(NWPU)Xi’an 710072China

The polarization effect introduced by electric field deformation is the most important bottleneck of CdZnTe detector in x-ray imaging. Currently, most of studies focus on electric field deformation caused by trapped carriers;the perturbation of electric field due to drifting carriers has been rarely reported. In this study, the effect of transient space-charge perturbation on carrier transport in a CdZnTe semiconductor is evaluated by using the laser-beam-induced current(LBIC) *** appear in the current curves of CdZnTe detectors with different carrier transport performances under intense excitation, indicating the deformation of electric field. The current signals under different excitations are compared. The results suggest that with the increase of excitation, the amplitude of cusp increases and the electron transient time gradually decreases. The distortion in electric field is independent of carrier transport performance of detector. Transient space-charge perturbation is responsible for the pulse shape and affects the carrier transport process.

关键词： CdZnTe transient space-charge perturbation laser-beam-induced current(LBIC) technique carrier transport

The impact of gut microbiota changes on the intestinal mucus barrier in burned mice:a study using 16S rRNA and metagenomic sequencing

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Burns & Trauma 2023年第1期11卷 842-856页

作者： Xule zha sen Su Dan Wu Panyang zha.g Yan Wei Shijun Fan Qianying Huang Xi Peng Clinical Medical Research Center Southwest HospitalThird Military Medical University(Army Medical University)Gaotanyan StreetShapingba DistrictChongqing400038China State Key Laboratory of Trauma Burns and Combined InjurySouthwest HospitalThird Military Medical University(Army Medical University)Chongqing400038China

Background:The gut microbiota is a complex ecosystem that plays a critical role in human health and ***,the relationship between gut microbiota and intestinal damage caused by burns is not well *** intestinal mucus layer is crucial for maintaining intestinal homeostasis and providing a physiological barrier against bacterial *** study aims to investigate the impact of gut microbiota on the synthesis and degradation of intestinal mucus after burns and explore potential therapeutic targets for burn ***:A modified histopathological grading system was employed to investigate the effects of burn injury on colon tissue and the intestinal mucus barrier in ***,16S ribosomal RNA sequencing was used to analyze alterations in the gut microbiota at days 1-10 *** on this,metagenomic sequencing was conducted on samples collected at days 1,5 and 10 to investigate changes in mucus-related microbiota and explore potential underlying ***:Our findings showed that the mucus barrier was disrupted and that bacterial translocation occurred on day 3 following burn injury in ***,the gut microbiota in mice was significantly disrupted from days 1 to 3 following burn injury,but gradually recovered to normal as the disease ***,there was a marked increase in the abundance of symbiotic and pathogenic bacteria associated with mucin degradation on day 1 after burns,but the abundance returned to normal on day ***,the abundance of probiotic bacteria associated with mucin synthesis changed in the opposite *** analysis revealed that after a burn injury,bacteria capable of degrading mucus may utilize glycoside hydrolases,flagella and internalins to break down the mucus layer,while bacteria that synthesize mucus may help restore the mucus layer by promoting the production of short-chain fatty ***:Burn injury leads to disruption of colonic mucus barrier an

关键词： Burn injury gut microbiota Intestinal mucus 16S rRNA Metagenomic sequencing

Hydrosilylation of olefins over rhodium complex anchored over thioether-functionalized MCM-41

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Chinese Chemical Letters 2010年第11期21卷 1310-1313页

作者： Lig Fang zha,Wei sen Yang,Wen Yan Hao,Ming Zhong Cai Department of Chemistry,Jiangxi Normal University,Nanchang 330022,China Department of Chemistry Jiangxi Normal University Nanchang 330022 China

The hydrosilylation of alkenes with triethoxysilane has been achieved at 120 C in the presence of 0.01 mol%of thioetherfunctionalized MCM-41 anchored rhodium complex,affording the corresponding addition products in 68-91%*** supported rhodium complex can be reused several times without noticeable loss of *** system not only solves the basic problems of catalyst separation and recovery,but also avoids the use of phosphine ligands.

关键词： Supported rhodium catalyst Sulfur rhodium complex Hydrosilylation MCM-41 Heterogeneous catalysis

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结合色彩补偿与双背景光融合的水下图像复原

光学精密工程 2024年第7期32卷 1059-1074页

作者：林森查子月沈阳理工大学自动化与电气工程学院辽宁沈阳110159

针对复杂成像环境下,水下图像存在颜色失真、细节模糊以及对比度低的问题,提出结合色彩补偿与双背景光融合的水下图像复原方法。通过分析光在水中的吸收衰减特性,提出改进的水下成像模型,基于Retinex理论与白平衡算法引入色彩补偿分量,... 详细信息

针对复杂成像环境下,水下图像存在颜色失真、细节模糊以及对比度低的问题,提出结合色彩补偿与双背景光融合的水下图像复原方法。通过分析光在水中的吸收衰减特性,提出改进的水下成像模型,基于Retinex理论与白平衡算法引入色彩补偿分量,降低水体背景颜色影响;根据背景光强度和颜色分布特性,提出双候选背景光融合方法,准确估计全局背景光;不依赖任何水体环境参数,根据背景颜色与散射系数的内在关系,采用引导-高通滤波,优化并增强各通道透射率;最后,逆求解成像模型复原水下图像。实验结果表明,在4个不同的水下数据集上与经典及新颖方法对比,所提方法恢复的图像颜色更自然,纹理细节更丰富清晰;色差值改善幅度达5.4%,UCIQE及FDUM指标提升幅度分别达8.3%和4.5%。所提方法在定性和定量实验中更具优势,能够显著提高水下图像质量。

关键词：水下图像复原色彩补偿背景光融合透射率估计

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四相8/6极双凸极永磁发电机运行分析

微特电机 2005年第3期33卷 15-17,23页

作者：查申森东南大学江苏南京210096

双凸极永磁电机是将开关磁阻电机与永磁材料相结合而派生出来的一种新型电机。文章建立了双凸极永磁发电机稳态运行时的数学模型,对不同整流装置、接不同性质负载时的稳态运行性能进行仿真,并将仿真结果与实验结果进行了比较。

关键词：双凸极永磁发电机数学模型稳态性能仿真

cDNA cloning,sequence analysis,and recombinant expression of akitonin beta,a C-type lectin-like protein from Agkistrodon acutus

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Acta Pharmacologica Sinica 2004年第3期25卷 118-123页

作者： Xiang-dong zha1,2,Jing LIU1,Kang-sen XU3 1 School of Life Science,University of Science and Technology,Hefei 230026 School of Life Science,Anhui University,2 Hefei 230039 National Institute for Control of Pharmaceuticals and Biological Products,Beijing 100050,China 3 School of Life Science University of Science and Technology Hefei 230026 National Institute for Control of Pharmaceuticals and Biological Products 北京 100050

AIM: To clone the cDNA of a new member of snake venom C-type lectin-like proteins, to study its structure- function relationships and to achieve its recombinant production. METHODS: PCR primers were designed based on the homology and cDNA was amplified by RT-PCR using total RNA from snake venom gland as the template. The PCR products were cloned into the plasmid pgEM-T and sequenced. The deduced protein sequence was analyzed with some bioinformatic programs. A recombinant expression plasmid was constructed using pBAD- TOPO as vector and transformed into *** TOP10 competent cells. RESULTS: A novel cDNA sequence encod- ing akitonin β was found and accepted by genBank (accession number AF387100). Akitonin β consists of a typical carbohydrate recognition domain (CRD) of C-type lectins, and it is homologous with other snake venom C-type lectin-like proteins. It was predicted to be a platelet antagonist. Upon induction with arabinose rAkitonin β express- ing in E coli was achieved at a high level (superior to 150 mg/L). The recombinant fusion protein exhibited inhibitory activities on rat platelet aggregation in vitro. CONCLUSION: A new member of snake venom C-type lectin-like proteins was discovered and characterized, and an efficient recombinant expression system was estab- lished for its production.

关键词： snake venoms cDNA akitonin C-type lectin-like proteins recombinant proteins structure- activity relationship

Numerical Study on Aerodynamic Performance of Floating Dual-Rotor Wind Turbines in Heave and Surge Motions

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China Ocean Engineering 2023年第6期37卷 1011-1021页

作者： WU Xiao-di LU Wen-hao WANg Kai HU Wei-fei FANg Jian-hao zha Ruo-si School of Ocean Engineering and Technology Sun Yat-sen University&Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519000China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310058China School of Mechanical Engineering Zhejiang UniversityHangzhou 310058China

Compared with the traditional wind turbine of a single rotor,dual-rotor wind turbines(DRWTs)have higher wind energy capture efficiency and a more complex ***,the aerodynamic performance of the DRWT installed on the floating platform will be greatly affected by the motion caused by wind and wave *** this paper,5 MW and 750 kW single rotor wind turbines(SRWTs)are combined into a 5 MW-5 MW DRWT and a 5 MW-750 kW DRWT,and their power output and wake field characteristics in different motions are *** flow field is obtained by solving the Reynolds-averaged Navier–Stokes equation(RANS).The overset grid technique is employed to achieve the large-amplitude multiple-degree-of-freedom motion of the *** overall performance of the 5 MW single rotor wind turbine is determined by a numerical *** the DRWTs,numerical results show that the surge motion and heave motion both have a negative effect on the power output of the *** surge motion is a critical factor that causes the power output of the DRWT to periodically change with *** average power output of the DRWT influenced by motion is lower than that of a DRWT with a fixed *** surge motion significantly disturbs the wake of the DRWT due to the mutual interference between the upstream and downstream *** the influence of heave motion,low-velocity regions downstream of the blade tip are *** study indicates that attenuating the surge and heave motion of offshore DRWT is very significant for improving its efficiency and should be taken into consideration during the design procedure.

关键词： DRWT surge motion heave motion wake field power output

Comparison of the signaling pathways of wing dimorphism regulated by biotic and abiotic stress in the brown planthopper

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Insect Science 2023年第4期30卷 1046-1062页

作者： Jing-Xiang Chen Wan-Xue Li Qin Su Jun Lyu Yi-Bing zha.g Wen-Qing zha State Key Laboratory of Biocontrol and School of Life Sciences Sun Yat-sen UniversityGuangzhouChina

Wing polymorphism is an evolutionary trait that is widely present in various insects and provides a model system for studying the evolutionary significance of insect *** brown planthopper(BPH,Nilaparvata lugens)can alter its wing morphs un-der biotic and abiotic ***,whether differential signaling pathways are induced by the 2 types of stress remain largely ***,we screened a number of candidate genes through weighted gene co-expression network analysis(WgCNA)and found that ornithine decarboxylase(NIODC),a key enzyme in the synthesis of polyamines,was as-sociated with wing differentiation in BPH and mainly responded to abiotic stress *** analyzed the Kyoto Encyclopedia of genes and genomes enrichment pathways of dif-ferentially expressed genes under the 2 stresses by transcriptomic comparison,and found that biotic stress mainly influenced insulin-related signaling pathways while abiotic stress mainly influenced hormone-related ***,we found that insulin receptor 1(NllnRI)may regulate wing differentiation of BPH by responding to both biotic and abiotic stress,but NllnR2 only responded to biotic ***,the juvenile hormone epoxide hydrolase associated with juvenile hormone degradation and NIODC may regu-late wing differentiation mainly through abiotic stress.A model based on the genes and stresses to modulate the wing dimorphism of BPH was *** findings present a comprehensive molecular mechanism for wing polymorphism in BPH induced by biotic and abiotic stress.

关键词： insulin juvenile hormone Nilaparvata lugens ornithine decarboxylase stress wing dimorphism

一种基于对数区间隔离森林的电力调度数据异常检测集成算法

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电网技术 2021年第12期45卷 4818-4827页

作者：王锋高欣贾欣任昺查森北京邮电大学现代邮政学院北京市海淀区100876 北京邮电大学人工智能学院北京市海淀区100876

准确的电力调度自动化系统异常检测对电力系统安全稳定运行有重要意义。该系统具有业务种类繁多、业务逻辑交互复杂等特点,带来了调度监测数据维度多、空间分布多样的特性;现有基于机器学习的离线数据异常检测方法,存在对局部异常等特... 详细信息

准确的电力调度自动化系统异常检测对电力系统安全稳定运行有重要意义。该系统具有业务种类繁多、业务逻辑交互复杂等特点,带来了调度监测数据维度多、空间分布多样的特性;现有基于机器学习的离线数据异常检测方法,存在对局部异常等特殊异常检测精度与检测效率难以有效兼顾等问题。提出了一种基于对数区间隔离的电力调度数据异常检测方法。针对数据维度之间的分布差异特性,运用马氏距离度量方法,基于每个样本点到数据分布中心的马氏距离,设计了对数区间隔离策略,构建多个子树,并将其整合成对数区间隔离森林异常检测器,筛选出数据集中的异常样本,兼顾检测精度和检测效率。公开数据集和某省级电网调度中心业务数据集作为训练与测试样本,验证了所提方法在异常检测AUC值等综合性能上的先进性及其在实际系统应用中的可行性。

关键词：电力调度自动化系统异常检测局部异常马氏距离集成学习对数区间隔离