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Synthesis of cyclicβ-silylenones via oxidative rearrangement of tertiaryα-hydroxy allylsilanes with PCC

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Chinese Chemical Letters 2011年第3期22卷 306-309页

作者： Xia Wu jian Lei zhen Lei Song Key Laboratory of Drug-Targeting of Education Ministry and Department of Medicinal Chemistry West China School of Pharmacy Sichuan University Chengdu 610041 China

An oxidative rearrangement of cyclic tertiary a-hydroxy allylsilanes has been carried out in refluxing ClCH_2CH_2Cl with pyridinium chlorochromate（PCC）.The reaction provides a convenient method to synthesize cyclic... 详细信息

关键词： Pyridinium chlorochromate Oxidative rearrangement Cyclicβ-silylenones

Kinetics of Catalysis-Driven Aggregation Processes with Sequential Input of Catalyst

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Communications in Theoretical Physics 2008年第1期49卷 235-238页

作者： CHEN Yu KE jian-Hong LIN zhen-Quan School of Physics and Electronic Information Wenzhou University Wenzhou 325027 China

We investigate the kinetic behavior of a two-species catalysis-driven aggregation model, in which coagulation of species A occurs only with the help of species B. We suppose the monomers of species B are stable and cannot selfcoagulate in reaction processes. Meanwhile, the monomers are continuously injected into the system. The model with a constant rate kernel is investigated by means of the mean-field rate equation. We show that the Mneties of the system depends crucially on the details of the input term. The injection rate of species B is assumed to take the given time- dependent form K（t） -t^λ, and the sealing solution of the duster size distribution is then investigated analytically. It is found that the cluster size distribution can satisfy the conventional or modified scaling form in most cases.

关键词： kinetic behavior catalysis aggregation scaling law

A NOVEL ALGORITHM FOR VOICE CONVERSION USING CANONICAL CORRELATION ANALYSIS

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Journal of Electronics(China) 2008年第3期25卷 358-363页

作者： jian Zhihua Yang zhen Institute of Signal Processing and Transmission Nanjing University of Post and Telecommunications Nanjing 210003 China

A novel algorithm for voice conversion is proposed in this paper. The mapping function of spectral vectors of the source and target speakers is calculated by the Canonical Correlation Analysis (CCA) estimation based on Gaussian mixture models. Since the spectral envelope feature remains a majority of second order statistical information contained in speech after Linear Prediction Coding (LPC) analysis, the CCA method is more suitable for spectral conversion than Minimum Mean Square Error (MMSE) because CCA explicitly considers the variance of each component of the spectral vectors during conversion procedure. Both objective evaluations and subjective listening tests are conducted. The experimental results demonstrate that the proposed scheme can achieve better per- formance than the previous method which uses MMSE estimation criterion.

关键词： Speech processing Voice conversion Canonical Correlation Analysis (CCA)

Hypermethylation of Syk gene in promoter region associated with oncogenesis and metastasis of gastric carcinoma

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World Journal of Gastroenterology 2004年第12期10卷 1815-1818页

作者： ShuiWang Yong-BinDing Guo-YuChen jian-GuoXia zhen-YanWu DepartmentofGeneralSurgery FirstAftiliatedHospitalofNanjingMedicalUniversityNanjing210029JiangsuProvinceChina

AIM: To investigate the rrelationship between methylation of Syk (spleen tyrosine kinase) gene in promoter region and oncogenesis, metastasis of gastric carcinoma. The relation between silencing of the Syk gene and methylation of Syk promoter region was also studied. METHODS: By using methylation-specific PCR (MSP) technique, the methylation of Syk promoter region in specimens from 61 gastric cancer patients (tumor tissues and adjacent normal tissues) was detected. Meanwhile, RTPCR was used to analyse syk expression exclusively. RESULTS: The expression of the Syk gene was detected in all normal gastric tissues. Syk expression in gastric carcinoma was lower in 14 out of 61 gastric cancer samples than in adjacent normal tissues (X^2=72.3, P<0.05). No methylation of Syk promoter was found in adjacent normal tissues, hypermethylation of Syk gene in promoter was detected 21 cases in 61 gastric carcinoma patients. The rate of methylation of Syk promoter in gastric carcinoma was higher than that in adjacent normal tissues (X^2=25.1, P<0.05). In 31 patients with lymph node metastasis, 17 were found with Syk promoter methylation. A significant difference was noted between two groups (X^2=11.4,P<0.05). CONCLUSION: Hypermethylation leads to silencing of the Syk gene in human gastric carcinoma. Methylation of Syk promoter is correlated to oncogenesis and metastasis of gastric carcinoma. Syk is considered to be a potential tumor suppressor and anti-metastasis gene in human gastric cancer.

关键词：基因肿瘤形成肿瘤转移胃癌甲基化

Novel Synthetic Method for Triacetylbenzene

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Chinese Chemical Letters 2006年第9期17卷 1165-1168页

作者： Bin ZHANG Yong GAO jian Li LI zhen SHI Department of Chemistry Northwest University Xi＇an 710069

Triacetylbenzene was prepared from tribenzimidazolium salt and Grignard reagent. The addition-hydrolysis reaction of tribenzimidazolium salt with Grignard reagent is reported and a novel method for preparation of tria... 详细信息

关键词： Triacetylbenzene tribenzimidazolium salt Grignard reagent synthesis.

Two-Dimensional Transition Metal Oxide and Chalcogenide-Based Photocatalysts

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Nano-Micro Letters 2018年第2期10卷 40-66页

作者： Farjana Haque Torben Daeneke Kourosh Kalantar-zadeh jian zhen Ou School of Engineering RMIT University

Two-dimensional(2D) transition metal oxide and chalcogenide(TMO&C)-based photocatalysts have recently attracted significant attention for addressing the current worldwide challenges of energy shortage and environmental pollution. The ultrahigh surface area and unconventional physiochemical, electronic and optical properties of 2D TMO&Cs have been demonstrated to facilitate photocatalytic applications. This review provides a concise overview of properties, synthesis methods and applications of 2D TMO&C-based photocatalysts. Particular attention is paid on the emerging strategies to improve the abilities of light harvesting and photoinduced charge separation for enhancing photocatalytic performances,which include elemental doping, surface functionalization as well as heterojunctions with semiconducting and conductive materials. The future opportunities regarding the research pathways of 2D TMO&C-based photocatalysts are also presented.

关键词： Hydrogen evolution reaction Pollutant degradation Water splitting Layered material Solar Carbon reduction

Development of a micro gas turbine combustor with T-type vaporizers

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航空动力学报 2007年第7期22卷 1118-1126页

作者： XU Quan-hong LIU Jun XU jian LIN Yu-zhen LIU Gao-en National Key Laboratory on Aero-Engines School of Jet PropulsionBeijing 13niversity of Aeronautics and Astronautics Beijing 100083 China

The study includes the experimental investigation of the evaporation performance of T-type vaporizer,mainly studied the relationship of the inlet air temperature and vaporizer wall temperature with the evaporation ***,it studied the LBO(lean blow out) and combustion efficiency of the micro aero-engine combustor with T-type vaporizer on the normal pressure test *** inlet air condition is environmental pressure and *** gas analysis method is used to study the combustion efficiency,and the inlet air temperature is 300 K,400 K and 500 *** could be concluded that the evaporation performance is improved with the increasing of the inlet air temperature and vaporizer wall temperature;the average LBO is 0.003;the combustion efficiency rises with the inlet air temperature,and it remain constant when the fuel/air ratio changed in the range from 0.008 to *** vaporization ratio is the key factor to determine the combustion performance.

关键词：离心式喷气发动机燃烧室喷雾器索特平均直径燃气涡轮

From arc-continent collision to ocean closure: Lower Cretaceous Shamuluo Formation in the western segment of the Bangong-Nujiang suture zone, central Tibet

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Geoscience Frontiers 2021年第5期12卷 309-326页

作者： An-Bo Luo jian-Jun Fan Bo-Chuan Zhang jian-zhen Zhang Hang Li Meng-Long Duan College of Earth Sciences Jilin UniversityChangchun 130061China Key Laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Natural ResourcesChangchun 130061China Hebei Institute of Regional Geological Survey Langfang 065000HebeiChina

One of most hotly debated topics concerning the Late Mesozoic evolution of Tethyan and the Tibetan Plateau is the timing of the closure of the Meso-Tethys ocean,which is represented by the Bangong-Nujiang suture *** Upper Jurassic-Lower Cretaceous Shamuluo Formation,which unconformably overlies the older Mugagangri Group accretionary complex,provides important information on the closure of the Meso-Tethys *** paper precisely confines the depositional age of the Shamuluo Formation in the western segment of the Bangong-Nujiang suture zone,extending it from the Late Jurassic to the *** with the results of previous studies,we suggest that the Shamuluo Formation in the Awengco-Baerqiong region mainly contains a bathyal Berriasian-Hauterivian subunit and a shallow-marine Albian *** analysis indicates that the Berriasian-Hauterivian subunit was mainly derived from the Jurassic southern Qiangtang magmatic arc,while the Albian subunit was derived from the coeval volcanic rocks and the Upper Carboniferous-Upper Permian strata in the southern Qiangtang ***,the two subunits of the Shamuluo Formation have significant distinct sedimentary facies and provenances,indicating that they were deposited in different tectonic *** on the regional geological data,we suggest that the bathyal Berriasian-Hauterivian subunit and the shallow-marine Albian subunit of the Shamuluo Formation should be interpreted as a record of the oceanic arc-continent collision and the Lhasa-Qiangtang soft-collision,***,the closure time of the Meso-Tethys Ocean is at least limited to the Albian.

关键词： Tibetan Plateau Meso-Tethys Ocean Shamuluo Formation Ocean closure Albian

Experimental study on smelting reduction of carbon-bearing manganese briquettes in slag bath

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Journal of Iron and Steel Research International 2018年第4期25卷 417-425页

作者： Bo Zhang Da-ping Wang Bin Chen zhen-jian Su zheng-liang Xue School of Metallurgical and Material Engineering Hunan University of Technology Zhuzhou 412007 Hunan China The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology Wuhan 430081 Hubei China

The reduction of carbon-bearing manganese briquettes in a slag bath was experimentally investigated at temperatures ranging from 1550 to 1650 ℃. Both the internal temperature and the microstructure evolution of the briquettes were analyzed by differential thermal analysis, scanning electron microscopy and energy-dispersive spectrum analysis, and the smelting reduction mechanism of the carbon-bearing manganese briquettes in the slag bath was further elaborated. The results indicated that the smelting reduction of the briquettes in the slag bath could be divided into three stages, and the aggregation and growth of the metallic particles during the reduction were significantly affected by the slag temperature. Under the experimental conditions, the reduction speed at the initial stage of the carbon-bearing manganese briquettes smelting reduction was controlled by the chemical reaction, whereas the reaction speeds at both the middle and following stages were limited by gaseous diffusion.

关键词： Slag bath Smelting reduction Carbon-bearing briquette Kinetics