检索结果-南通市图书馆

Parameterized expressions for an improved Rouse equation

International Journal of Sediment Research 2013年第4期28卷 523-534页

作者： Chen CHENG Zhi-yao SONG yi-gang WANG jin-shan ZHANG School of Marine Sciences Nanjing University of Information Science&Technology Key Laboratory of Virtual Geographic Environment under Ministry of Education and Jiangsu Key Laboratory for Numerical Simulation of Large-Scale Complex SystemNanjing Normal University College of Harbor Coastal and Offshore EngineeringHohai University River Harbor Engineering Department Nanjing Hydraulic Research Institute

The equilibrium profile of suspended sediment concentration（SSC） in steady,uniform turbulent flow has been extensively studied since the proposition of Rouse equation（Rouse,1937）.Many researchers keep studying and attempting to improve the Rouse equation by modifying the mixing length *** and Dey（2009） improved Rouse equation based on the modified sediment diffusivity,however,their proposed sediment diffusivity has two parameters,the depth modification factor α and the reciprocal of the sediment Schmidt number β=1/S;,and the corresponding expressions were not given properly in their *** paper aims to parameterize the relevant coefficients,the results shows:（1）α is parameterized from a reasonable approximation by the analysis of surface boundary condition of SSC;（2） considering some effect factors on the settling velocity,β can be expressed by an extended and modified Montcs-Ippen formula,and its related parameters are calibrated by substantial data about the relationship between the primary Rouse parameter Z.= ω;/*** its counterpart Z.’=ω;/β*** verification with some experimental and field datasets,and comparison with related formula,the results show that the sediment diffusivity and SSC profiles have a good agreement with measured data used the present parameterized expressions of a and β,so the present improved Rouse equation is reasonable,and can be applied in practical ***,an approximation and simplified expression of the improved Rouse equation is deduced by using the approach of perturbation,which can be applied easily for the estimation of suspended sediment transport rate.

关键词： Improved Rouse equation Parameterization Sediment transport

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Pretreating near infrared spectra with fractional order Savitzky–Golay differentiation(FOSGD)

引用

Chinese Chemical Letters 2015年第3期26卷 293-296页

作者： Kai-yi Zheng Xuan Zhang Pei-jin Tong Yuan yao yi-Ping Du Shanghai Key Laboratory of Functional Materials Chemistry and Research Centre of Analysis and TestEast China University of Science and Technology Department of Chemical Engineering National Tsing Hua University

With the aid of Riemann–Liouville fractional calculus theory,fractional order Savitzky–Golay differentiation（FOSGD） is calculated and applied to pretreat near infrared（NIR） spectra in order to improve the performance of multivariate *** to integral order Savitzky–Golay differentiation（IOSGD）,FOSGD is obtained by fitting a spectral curve in a moving window with a polynomial function to estimate its coefficients and then carrying out the weighted average of the spectral curve in the window with the *** NIR datasets including diesel,wheat and corn datasets were utilized to test this *** results showed that FOSGD,which is easy to compute,is a general method to obtain Savitzky–Golay smoothing,fractional order and integral order *** order differentiation computation to the NIR spectra often improves the performance of the PLS model with smaller RMSECV and RMSEP than integral order ones,especially for physical properties of interest,such as density,cetane number and hardness.

关键词： Golay FOSGD fractional fitting smoothing utilized compute polynomial Liouville calibration

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Intermediates transformation for efficient perovskite solar cells

引用

Journal of Energy Chemistry 2021年第1期30卷 102-114,I0004页

作者： Zhizai Li yi Sun Huanhuan yao jing Zhao Qian Wang Liming Ding Zhiwen jin School of Physical Science and Technology&Key Laboratory for Magnetism and Magnetic Materials of MoE&Key Laboratory of Special Function Materials and Structure Design MoE&National&Local Joint Engineering Laboratory for Optical Conversion Malerials and TechnologyLanzhou UniversiyLanzhou 730000 GansuChina School of Physics Changhi UnversityChornghi 830100 Xinjiang Uygur Autonomous RegionChina Center for Excllence in Nanoscience(CAS) Key Laboratony of Nonosystem anp Hierarchical Fabrication(CAS)Nationol Center for Nanoscience and TechnologyBeijing 100190China

Perovskite materials have made a great progress in terms of the power conversion efficiency(PCE), rising from 3.8% to 25.2%. To obtain pinhole-free, superior crystal, and high-quality perovskite films with less defect, intermediates transformation is important, which has been clearly studied and widely *** this review, we systematically summarize the commonly formed intermediates and detailedly analyze their mechanisms from five aspects:(1) Solvent-induced intermediate;(2) HI-induced intermediate;(3)CH3NH2-induced intermediate;(4) MAAc-induced intermediate;(5) other intermediates. Finally, we also provide some prospects on high-quality perovskite fabrication based on using intermediates prudently.

关键词： Intermediate Formation energy Crystalline dynamics Solubility Nucleation sites

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Flexible carbon fiber-based composites for electromagnetic interference shielding

引用

Rare Metals 2022年第11期41卷 3612-3629页

作者： Hong-Yan Zhang jin-yao Li ying Pan yi-Fan Liu Nasir Mahmood Xian Jian School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu611731China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China RMIT University School of EngineeringMelbourneVic3001Australia

With the rapid development of electronic information technology,the waste electromagnetic radiation generated by the wireless and various other electronic devices has caused serious harm to human *** development of high-efficiency flexible electromagnetic interference(EMI)shielding materials has become one of the most effective ways to mitigate the increasingly serious problem of electromagnetic *** carbon fiber composites possess most of the physical requirements needed for EMI shielding applications,including high electrical conductivity,large specific surface area,light weight,flexibility,porous structure,and adjustable physical and chemical properties,and various morphology of carbon fibers-based composites applied *** this review,the primary EMI shielding mechanism of carbonfiber-based materials is *** carbon fiber suffers from a low absorption efficiency when used for EMI shielding by itself,it is usually combined with additional EMI filling ***,the methods of adding EMI filler materials to the carbon fiber framework and the influence of different fillers on the EMI shielding performance are also *** addition,the novel structural designs of flexible carbon fiber-based EMI shielding materials,including fiber orientation,core-shell structure,and multilayer heterostructure,are summarized in terms of their classification,which includes composites with metal,polymer,nano-carbon,and *** review concludes with a brief discussion of the challenges,research directions,and future prospects of carbon-fiber-based EMI shielding materials.

关键词： Carbon fibers Electromagnetic interference shielding Flexible Composites

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Trans-anal minimally invasive surgery for rectal neoplasia:Experience from single tertiary institution in China

引用

World Journal of Gastrointestinal Oncology 2018年第6期10卷 137-144页

作者： Nan Chen yi-Fan Peng Yun-Feng yao jin Gu Department of Gastrointestinal Center Unit Ⅲ Peking University Hospital and InstituteBeijing 100142China

AIM To evaluate the feasibility and safety of trans-anal minimally invasive surgery(TAMIS) from single institute in China. METHODS A retrospective review was conducted for patients with rectal neoplasia, who underwent TAMIS using single incision laparoscopic surgery-Port from January 2013 till January 2016 by a group of colorectal surgeons from Gastrointestinal Center Unit Ⅲ, Peking University Cancer Hospital. Patients' demographic data, surgical related information, post-operational pathology, as well as perioperative follow-up were all collected. RESULTS Twenty-five patients with rectal neoplasia were identified consequently. Complete full-thickness excision was achieved in all cases without conversion. 22(88%) cases had rectal malignancies [6 were adenocarcinomas and 16 were neuroendocrine tumors(NET)], while 3 patients had adenomas. Mean surgical duration was 61.3 min, and mean post-operative stay were 2.7 d. Post-operational examination demonstrated 5 cases had positive resection margin: 2 adenocarcinoma cases and 1 NET case with positive lateral margin, and the other 2 NET cases with positive basal margin. The curve of operation time for TAMIS cases suggested a minimum of 10 cases for a laparoscopic surgeon proficient withthis technique. CONCLUSION TAMIS was demonstrated to be reproducible and safe,with a relatively short learning process for laparoscopic surgeons in selected cases for rectal neoplasia. Longterm oncological outcome needs to be determined by further investigation.

关键词： Rectal neoplasia Resection margin Transanal minimally invasive surgery

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

In vitro induction and differentiation of umbilical cord mesenchymal stem cells into neuron-like cells by alltrans retinoic acid

引用

International Journal of Ophthalmology(English edition) 2015年第2期8卷 250-256页

作者： Wei jin yao-Peng Xu An-Huai Yang yi-Qiao Xing Eye Center Renmin Hospital of Wuhan University Department of Urology Wuhan General Hospital of Guangzhou Military Command

AIM: To determine the optimal concentration for inducing the differentiation of human umbilical cord-derived mesenchymal stem cells(h UC-MSCs) into neuron-like cells, although it is understood that all-trans retinoic acid(ATRA) regulates cell proliferation in the nervous system by modulating the balance between mitosis and ***: The abilities of ATRA to promote apoptosis as well as neural differentiation were assessed in cultured h UC-MSCs by morphological observation, MTT assay, annexin V-FITC/PI flow cytometry and ***: The data showed that low concentrations of ATRA(0.5 μmol, 0.25 μmol) had no effect on the number of cells. However, treatment with 1.0 μmol or 2.0 μmol ATRA induced a 24.16% and 52.67% reduction in cell number, respectively, compared with vehicle-treated cultures. Further, 4.0 μmol ATRA had a potent effect on cell number, with almost no adherent cells recovered after 24 h. We further showed that 0.5 μmol ATRA caused these cells to express characteristic markers of neuronal progenitor ***: Taken together, we conclude that ATRA has a dose-dependent influence on the neural differentiation and apoptosis of h UC-MSCs. These findings have implications on the use of ATRA-differentiated h UC-MSCs for the study of neural degeneration diseases.

关键词： human umbilical cord mesenchymal stem cells differentiation apoptosis neuron-like cells

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Shor's algorithm does not factor large integers in the presence of noise

引用

Science China(Information Sciences) 2024年第7期67卷 305-320页

作者： jin-yi CAI College of Letters and Science University of Wisconsin

We consider Shor's quantum factoring algorithm in the setting of noisy quantum gates. Under a generic model of random noise for(controlled) rotation gates, we prove that the algorithm does not factor integers of the form pq when the noise exceeds a vanishingly small level in terms of n—the number of bits of the integer to be factored, where p and q are from a well-defined set of primes of positive density. We further prove that with probability 1-o(1) over random prime pairs(p, q), Shor's factoring algorithm does not factor numbers of the form pq, with the same level of random noise present.

关键词： random noise Shor's algorithm rotation gates quantum computing prime factorization

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Effect of mechanical alloying on sinterability and phase evolution in pressure-less sintered TiB_(2)-TiC ceramics

引用

Journal of Materiomics 2019年第4期5卷 670-678页

作者： Tian-yi Hu Mian-yi yao Dong-Li Hu Hui Gu Yu-jin Wang Materials Genome Institute School of Materials Science and EngineeringShanghai UniversityShanghai200444China Institute for Advanced Ceramics School of Materials Science and EngineeringHarbin Institute of Technology150080China Key Laboratory of Advanced Structure Function Integrated Materials and Green Manufacturing TechnologyMinistry of Industry and Information TechnologyHarbin Institute of TechnologyHarbin150001China

Phase relation and microstructure evolution in the pressure-less sintered TiB_(2)‒TiC ceramics preceded with mechanical alloying were systematically studied by a combination of SEM *** debris from milling balls promotes sintering by dissolving into the TiC phase to achieve dense microstructures at 1600℃.Variation of W solution in TiC grains exposes two types of core-rim structures,with no or more W in dark and white cores respectively but with common medium W in both *** whitecores reveal an exchange reaction between WC and TiC via mechanical alloying to form the Ti_(1-z)W_(z)C phase prior to *** dark-cores inherit from the as-milled TiC power to further enable the reprecipitation of rims from a mixed liquid-phase,which facilitated also the anisotropic growth of TiB_(2) *** dark-cores grow persistently in the second-step at 2000℃ enabled by this liquid-phase,which coarsens the TiB2 grains *** more alloyed phase,sintering was insufficient at 1500℃ with only the surface fluidity from the primary powders,and the second-step sintering increased the fluidity in the liquid-phase to fully densify the binary ***-distribution of the alloyed W by two-step sintering rationalizes the evolution process of the binary microstructures and leads to better understanding of the mechanical behaviors.

关键词： TiB2‒TiC ceramics Mechanical alloying Core‒rim structures Liquid-phase sintering Microstructure‒Property relationship

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Influence of counteranions on catalytic ability of immobilized laccase in Cu-alginate matrices: Inhibition of chloride and activation of acetate

引用

Chinese Chemical Letters 2014年第7期25卷 983-988页

作者： Ting Pan yao-jin Sun Xiao-Lei Wang Ting Shi yi-Lei Zhao State Key Laboratory of Microbial Metabolism School of Life Sciences & BiotechnologyShanghai Jiao Tong University

Laccase is a promising oxidase with environmental applications, such as lignin degradation and chlorophenol detoxification. Laccase immobilization can significantly improve physiochemical stability and reusability compared to the free enzymes. In this work, anion effect was investigated in entrapment of Cu-alginate matrix with five types of anions, including perchlorate （ClO4）, nitrate （NO3）, sulfate （SO42 ）, chloride （Cl）, and acetate （CH3CO2-）. Accordingly, chloride inhibition and acetate activation were detected in the o-tolidine kinetic experiments, while effects of the other three anions were much smaller. Such counteranion effects were also observed in the laccase-catalyzed biodegradation of 2,4- dichlorophenol. The results indicated that counteranions in the enzyme immobilization process are crucial for catalytic capacity, probably due to the competition with the carboxylate groups in alginate. Our results also imply that these anions might coordinate the copper cations in laccase.

关键词： Counterion effect Cu-alginate matrix Laccase immobilization Enzyme activity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

纳米ZnO在抗菌拒水拒油整理方面的应用研究

引用

染整技术 2005年第1期27卷 13-15页

作者：赵晓娣姚金波丁毅府佳萍天津工业大学材料与化工学院天津300160

通过纳米ZnO与拒水拒油整理剂之间的协同作用,对棉绒织物实施抗菌整理加工。并介绍了纳米氧化锌的抗菌机理、偶联荆的偶联机理以及整理液的制备方法,通过拒水拒油性能的测试优化出最佳工艺,借助拒水拒油的作用来防止细菌的粘附,从而进... 详细信息

通过纳米ZnO与拒水拒油整理剂之间的协同作用,对棉绒织物实施抗菌整理加工。并介绍了纳米氧化锌的抗菌机理、偶联荆的偶联机理以及整理液的制备方法,通过拒水拒油性能的测试优化出最佳工艺,借助拒水拒油的作用来防止细菌的粘附,从而进一步提高织物的抗菌性能。

关键词：纳米ZnO 抗菌拒水拒油偶联剂

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：