检索结果-南通市图书馆

Thermoregulated Organic Biphasic Hydrogenation of 1-Octene Catalyzed by Ru/PETPP Complex

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2006年第2期17卷 255-257页

作者： Ya Dong LU Yan Hua WANG Zi Lin jin State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012

Thermoregulated organic biphasic system composed of triethylene glycol monomethyl ether （TGME） and n-heptane was first applied to the hydrogenation of 1-octene. Under the optimal conditions： P（H2）=5.0MPa, T=80℃, t=3h, 1-octene/Ru=1000 （molar ratio）, the yield of n-octane reached up to 99.6%. Furthermore, the simply decanted catalyst could be reused for 10 times without apparent loss of catalytic activity.

关键词： Thermoregulated organic biphasic system hydrogenation 1-octene ruthenium.

Calculation Models of Interlamellar Spacing of Pearlite in High-Speed 82B Rod

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2008年第4期15卷 57-60页

作者： XU jin-qiao LIU Ya-zheng ZHOU Shu-mei School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

With the investigated subject of 82B rod, the interlamellar spacings of pearlite at different isothermal transformation temperatures and different cooling rates during continuous cooling transformation were measured, and the effect of the isothermal transformation temperature and cooling rate on the interlamellar spacing was analyzed quantitatively. Moreover, the relationship models between undercooling and interlamellar spacing were presented by data regression. The experimental results show that the relationship between undercooling and reciprocal interlamellar spacing remains linear when the undercooling is not very large, or else, the interlamellar spacing tends to be constant and the relationship will deviate from linearity.

关键词： interlamellar spacing calculation model high-speed rod 82B

Soliton Solutions for Nonisospectral AKNS Equation by Hirota＇s Method

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2006年第3期45卷 398-400页

作者： BI jin-Bo SUN Ye-Peng CHEN Deng-Yuan Department of Mathematics Shanghai University Shanghai 200444 China

Bilinear form of the nonisospectral AKNS equation is given. The N-soliton solutions are obtained through Hirota＇s method.

关键词： nonisospectral AKNS equation soliton solutions Hirota's method

Dynamics of an SIRS model with age structure and two delays

在线全文

学校读者我要写书评

暂无评论

International Journal of Biomathematics 2021年第7期14卷 145-162页

作者： Hongquan Sun Hong Li jin Li Zhangsheng Zhu School of Mathematics and Physics Jiangsu University of Technology Changzhou 213001 P.R.China School of Science Jiuyjiang University Jiujiang 332005P.R.China

ln this paper,we propose and investigate an SlRS model with age structure and *** the infected and the recovered individuals have age structure,the infectionrate(from the infective to the susceptible)and the immune loss rate(from the recoveredto the susceptible)are related to two independent time delays,*** provethat the proposed age structured SIRS model is well-posed by using the *** basic reproduction number Ro is given,and the unique endemic equilib-rium exists when R_(0)>1,while the disease-free equilibrium always exists.A rigorousmathematical analysis for the stability of two equilibria is *** disease-freeequilibrium is local asymptotically stable if R_(0)1 and τl=***,we give numerical simulations toverify our results.

关键词： Infectious disease model SIRS model age structure delay stability

Adaptive Iterative Learning Control Based on Unfalsified Strategy for Chylla-Haase Reactor

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

IEEE/CAA Journal of Automatica Sinica 2014年第4期1卷 347-360页

作者： jing Wang Yue Wang Liulin Cao Qibing jin the College of Information Science and Technology Beijing University of Chemical Technology

An adaptive iterative learning control based on unfalsified strategy is proposed to solve high precision temperature tracking of the Chylla-Haase reactor, in which iterative learning is the main control method and the unfalsified strategy is adapted to adjust the learning rate adaptively. It is encouraged that the unfalsified control strategy is extended from time domain to iterative domain, and the basic definition and mathematics description of unfalsified control in iterative domain are *** proposed algorithm is a kind of data-driven method, which does not need an accurate system model. Process data are used to construct fictitious reference signal and switch function in order to handle different process conditions. In addition, the plant data are also used to build the iterative learning control law. Here the learning rate in a different error level is adjusted to ensure the convergent speed and stability, rather than keeping constant in traditional iterative learning control. Furthermore,two important problems in iterative learning control, i.e., the initial control law and convergence analysis, are discussed in detail. The initial input of first iteration is arranged according to a mechanism model, which can assure a good produce quality in the first iteration and a fast convergence speed of tracking error. The convergence condition is given which is obviously relaxed compared with the tradition iterative learning *** results show that the proposed control algorithm is effective for the Chylla-Haase problem with good performance in both convergent speed and stability.

关键词： Inductors Polymers Heat transfer Cooling Process control Mathematical model Learning (artificial intelligence) Iterative methods Temperature measurement

Balanced pulses in two outputs of quantum photonic chip

在线全文

学校读者我要写书评

暂无评论

Optoelectronics Letters 2021年第10期17卷 592-597页

作者： YOU jin WANG Yue AN Junming State Key Laboratory of Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Silica planar lightwave circuit(PLC) devices can offer great potential for quantum key distribution(QKD) with benefits of low-loss, low-cost, large-scale integration, miniaturization, stability and mass production. A complementary encoding-decoding system for QKD based on silica PLC technology was demonstrated, achieving two channels that have balanced outputs simultaneously. This system is consisted of two chips, and each chip is consisted of a variable optical splitter(VOS), an asymmetric Mach-Zehnder interferometer(AMZI) with a thermo-optic phase modulator(TOPM), a delay line(DL), and a directional coupler(DC). The measured delay times of pulse-pairs for two chips are 396 ps and 398 ps, respectively, and the system has shown relatively high interference visibility(IV) of 93.5% and 91.3% for two channels, respectively.

关键词： interferometer modulator quantum

Estimator of a change point in single index models

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2014年第8期57卷 1701-1712页

作者： jin BaiSuo DONG CuiLing TAN ChangChun MIAO BaiQi Department of Statistics and Finance University of Science and Technology of China School of Mathematical Sciences Xinjiang Normal University School of Mathematics Hefei University of Technology

This paper considers the problem of change point in single index *** order to obtain asymptotically valid confidence intervals for the estimation of the change point,the convergence rate and asymptotic distribution of the change point estimate is *** simulation results are presented which show that the numerical performance of our estimator is satisfactory.

关键词： single index model change point convergence rate asymptotic distribution

One-half layer pancreaticojejunostomy with the rear wall of the pancreas reinforced:A valuable anastomosis technique

在线全文

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2022年第26期10卷 9276-9284页

作者： jin-Ping Wei Sheng Tai Zhi-Lei Su Department of General Surgery Beijing Chuiyangliu HospitalBeijing 100022China Department of Hepatopancreatobiliary Surgery The Second Affiliated Hospital of Harbin Medical UniversityHarbin 150086Heilongjiang ProvinceChina

BACKGROUND Postoperative pancreatic fistula(POPF)is one of the most common and serious complications after pancreaticoduodenectomy(PD).To effectively reduce the incidence of POPF,we designed a new type of pancreaticojejunostomy(PJ),which was termed one-half layer PJ with the rear wall of the pancreas *** To explore the clinical application value of this new *** We compared 62 patients who had undergone PD by either the traditional ductto-mucosa anastomoses or the new one-half layer PJ with the rear wall of the pancreas reinforced method at our hospital from May 2015 to September *** 62 patients were operated by the same surgeon experienced in both *** retrospectively analyzed patient characteristics,perioperative outcomes,and surgical *** There was no significant difference between the two groups in basic information except the postoperative hospital stays,14.7±5.4 d in the traditional duct-tomucosa anastomoses group and 12.0±4.2 d in the one-half layer PJ group(P=0.042).In terms of postoperative complications,the one-half layer PJ group had a lower rate of POPF than the traditional *** overall number of cases with POPF was 8(24.2%)in the traditional group and 2(6.9%)in the one-half layer group(P=0.017).Additionally,the rate of grades B and C POPF was lower in the one-half layer group(3.4%)compared with that(12.1%)in the traditional group(P=0.010).One patient died due to hemorrhage caused by severe pancreatic fistula in the traditional *** One-half layer PJ with the rear wall of the pancreas reinforced is a safe and feasible procedure that can successfully reduce the rate of *** may be a promising technique for PJ after PD.

关键词： Pancreaticoduodenectomy Pancreaticojejunostomy Pancreatic fistula One-half layer New technique Postoperative complications

Microfluidic System for Synthesis of Trigonal Selenium Nanowires

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

Chemical Research in Chinese Universities 2010年第4期26卷 522-526页

作者： BIAN Tian-bin YIN Xue-feng LIU jin-hua Institute of Microanalytical Systems Department of Chemistry Zhejiang University Hangzhou 310027 P. R. China College of Material Chemistry and Chemical Engineering Hangzhou Normal University Hangzhou 310036 P. R. China

A microfluidic system was developed for the synthesis of trigonal selenium（t-Se） nanowires, which was composed of a glass microchip coupled with a poly（methyl methacrylate）（PMMA） microchip. In the glass microchip, amorphous selenium（a-Se） colloid was prepared by reducing selenious acid with an excess amount of hydrazine at a temperature of 100 ℃. In the coupled PMMA microchip, a-Se was transformed into more stable t-Se seeds via sonication at room temperature. The residence time of the reactants in both microchips was optimized by varying the dimension and length of the microchannel each. The t-Se nanowires were formed by anisotropic growth of selenium crystallite during sonication and aging under the assistance of β-cyclodextrin（β-CD）. Various stages of the nanowires＇ growth were investigated. The as-synthesized products were characterized by powder X-Ray diffraction（XRD）, Raman spectroscopy, scanning electron microscopy（SEM）, transmission electron microscopy（TEM） and selected-area electron diffraction（SAED）.

关键词： Microfluidic Trigonal selenium nanowire Sonication