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Analyzing the Flavor Compounds in Chinese Traditional Fermented Shrimp Pastes by HS-SPME-GC/MS and Electronic Nose

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Journal of Ocean University of China 2017年第2期16卷 311-318页

作者： FAN Yan yin Li-ang XUE Yong LI Zhaojie HOU Hu XUE Changhu College of Food Science and Engineering Ocean University of ChinaQingdao 266003P.R.China

Shrimp paste is a type of condiments with high nutritional ***,the flavors of shrimp paste,particularly the non-uniformity flavors,have limited its application in food *** order to identify the characteristic flavor compounds in Chinese traditional shrimp pastes,five kinds of typical commercial products were evaluated in this *** differences in the volatile composition of the five products were *** phase micro-extraction method was employed to extract the volatile ***-MS and electronic nose were applied to identify the compounds,and the data were analyzed using principal component analysis(PCA).A total of 62 volatile compounds were identified,including 8 alcohols,7 aldehydes,3 ketones,7 ethers,7 acids,3 esters,6 hydrocarbons,12 pyrazines,2 phenols,and 7 other *** typical volatile compounds contributing to the flavor of shrimp paste were found as follows:dimethyl disulfide,dimethyl tetrasulfide,dimethyl trisulfide,2,3,5-trimethyl-6-ethyl pyrazine,ethyl-2,5-dimethyl-pyrazine,phenol and *** acid,butanoic acid,furans,and 2-hydroxy-3-pentanone caused unpleasant odors,such as pungent and rancid *** component analysis showed that the content of volatile compounds varied depending on the processing conditions and shrimp *** results indicated that the combinations of multiple analysis and identification methods could make up the limitations of a single method,enhance the accuracy of identification,and provide useful information for sensory research and product development.

关键词： volatile flavor compounds GC-MS electronic nose sensory analysis

Identification of Fucans from Four Species of Sea Cucumber by High Temperature ~1H NMR

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Journal of Ocean University of China 2014年第5期13卷 871-876页

作者： WU Nian CHEN Shiguo YE Xingqian LI Guoyun yin Li'ang XUE Changhu College of Biosystem Engineering and Food Science Zhejiang University College of Food Science and Engineering Ocean University of China

Acidic polysaccharide, which has various biological activities, is one of the most important components of sea cucumber. In the present study, crude polysaccharide was extracted from four species of sea cucumber from three different geographical zones, Pearsonothuria graeffei(Pg) from Indo-Pacific, Holothuria vagabunda(Hv) from Norwegian Coast, Stichopus tremulu(St) from Western Indian Ocean, and Isostichopus badionotu(Ib) from Western Atlantic. The polysaccharide extract was separated and purified with a cellulose DEAE anion-exchange column to obtain corresponding sea cucumber fucans(SC-Fucs). The chemical property of these SC-Fucs, including molecular weight, monosaccharide composition and sulfate content, was determined. Their structure was compared simply with fourier infrared spectrum analyzer and identified with high temperature 1H nuclear magnetic resonance spectrum analyzer(NMR) and room temperature 13 C NMR. The results indicated that Fuc-Pg obtained from the torrid zone mainly contained 2,4-O-disulfated and non-sulfated fucose residue, whereas Fuc-Ib from the temperate zone contained non-, 2-O- and 2,4-O-disulfated fucose residue; Fuc-St from the frigid zone and Fuc-Hv from the torrid zone contained mainly non-sulfated fucose residue. The proton of SC-Fucs was better resolved via high temperature 1H NMR than via room temperature 1H NMR. The fingerprint of sea cucumber in different sea regions was established based on the index of anomer hydrogen signal in SC-Fucs. Further work will help to understand whether there exists a close relationship between the geographical area of sea cucumber and the sulfation pattern of SC-Fucs.

关键词： sea cucumber sulfated fucan composition analysis 1H NMR identification

Cyclic-delay time-reversal space-time block codes for single-carrier transmission with frequency-domain decision-feedback equalization

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Science China(Information Sciences) 2011年第9期54卷 1905-1915页

作者： FENG ang,yin QinYe & Wang HuiMing MOE Key Laboratory for Intelligent Networks and Network Security,Xi’an Jiaotong University,Xi’an 710049,China 1. MOE Key Laboratory for Intelligent Networks and Network Security Xi’an Jiaotong University Xi’an 710049 China

Transmit diversity is an important multiple-input multiple-output (MIMO) approach to improve the transmission reliability;however,it is usually designed with maximum-likelihood *** this paper,we investigate a simple transceiver structure for single-carrier MIMO systems,in which the cyclic-delay time-reversal space-time block code (CDTR-STBC) is employed at the transmitter,and the frequency-domain decision-feedback equalization (FD-DFE) is used at the *** separate the transmit antennas into two groups,and then,encode the groups by STBC and cyclically delay the data streams within each *** processing can mitigate the impact of error-propagation and reduce the signal-to-noise ratio (SNR) loss when FD-DFE is employed,in which SNR is defined as the ratio of the received signal power over the noise power at each receive *** support our proposal,this paper also provides the performance analysis of *** is shown that the proposed scheme can achieve full diversity and full transmission rate for a MIMO system employing arbitrary ***,it has considerable performance improvement over the existing schemes.

关键词： single-carrier frequency-domain equalization cyclic delay space-time block code diversity order

Optimization of sodium hydroxide for securing high thermoelectric performance in polycrystalline Sn1−xSe via anisotropy and vacancy synergy

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InfoMat 2020年第6期2卷 1201-1215页

作者： Xiao-Lei Shi Wei-Di Liu ang-yin Wu Van TNguyen Han Gao Qiang Sun Raza Moshwan Jin Zou Zhi-Gang Chen Centre for Future Materials University of Southern QueenslandSpringfield CentralQueenslandAustralia Materials Engineering The University of QueenslandBrisbaneQueenslandAustralia Centre for Microscopy and Microanalysis The University of QueenslandBrisbaneAustralia

The morphology and composition are two key factors to determine the thermoelectric performance of aqueously synthesized tin selenide(SnSe)crystals;however,their controlling is still under *** this study,we report a high figure-of-merit(ZT)of1.5 at 823 K in p-type polycrystalline Sn1−xSe resulted from a synergy of morphology control and vacancy optimization,realized by carefully tuning the sodium hydroxide(NaOH)concentration during solvothermal *** a comprehensive investigation on various NaOH concentrations,it was found that an optimized NaOH amount of 10 mL with a concentration of 10 mol L^−1 can simultaneously achieve a large average crystal size and a high Sn vacancy concentration of2.5%.The large microplate-like crystals lead to a considerable anisotropy in the sintered pellets,and the high Sn vacancy level contributes to an optimum hole concentration to the level of2.3×10^19 cm^−3,and in turn a high power factor of7.4μW cm^−1 K^−2 at 823 K,measured along the direction perpendicular to the sintering *** addition,a low thermal conductivity of0.41 W m^−1 K^−1 is achieved by effective phonon scattering at localized crystal imperfections including lattice distortions,grain boundaries,and vacancy domains,as observed by detailed structural ***,a competitive compressive strength of52.1 MPa can be achieved along the direction of high thermoelectric performance,indicating a mechanically robust *** study provides a new avenue in achieving high thermoelectric performance in SnSe-based thermoelectric materials.

关键词： anisotropy sodium hydroxide thermoelectric tin selenide vacancy

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经编单向导湿织物设计与结构优化

纺织学报 2023年第4期44卷 86-91页

作者：尹昂丛洪莲江南大学教育部针织技术工程研究中心江苏无锡214122

为探究经编结构和原料配置对织物单向导湿性能的影响,对织物各梳栉的调整、原料的配置和织物结构进行选择。设计8个样品,通过对其水分管理性能研究对比后发现,内层纱线和外层纱线线密度差异越大,织物的单向导湿性能就越好。在原料配置方... 详细信息

为探究经编结构和原料配置对织物单向导湿性能的影响,对织物各梳栉的调整、原料的配置和织物结构进行选择。设计8个样品,通过对其水分管理性能研究对比后发现,内层纱线和外层纱线线密度差异越大,织物的单向导湿性能就越好。在原料配置方面,内侧选用5.6 tex(14 f)涤纶低弹丝,外侧选用8.3 tex(288 f)的涤纶低弹丝具有最佳的水分管理性能;而内层选用5.6 tex(14 f)的涤纶低弹丝,外层选用9.7 tex的棉纱具有较高的润湿时间和吸收率,但其内外层润湿时间差、最大润湿半径和扩散速度较低,会影响面料对人体的穿着舒适度。在结构方面,外层采用经绒组织,内层采用编链,其整体水分管理性能要优于内层采用经缎组织,且织物内层纱线垫纱成圈织针数越少有利于增强单向导湿性能。

关键词：经编单向导湿原料配置织物结构差动毛细效应针织物设计

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二维升降法

航空学报 1998年第6期19卷 748-753页

作者：傅惠民殷刚北京航空航天大学固体力学研究所

提出了一种二维升降法，该方法不仅适用于极小样本情况，而且还可以综合利用以往积累的试验数据和当前的试验数据来预测敏感性变量的百分位值（安全疲劳极限、安全冲击强度等）和百分率（可靠度、破坏率等）。与传统的只能利用当前试验... 详细信息

提出了一种二维升降法，该方法不仅适用于极小样本情况，而且还可以综合利用以往积累的试验数据和当前的试验数据来预测敏感性变量的百分位值（安全疲劳极限、安全冲击强度等）和百分率（可靠度、破坏率等）。与传统的只能利用当前试验数据的升降法相比，其可利用的信息量有了大幅度增加，所以，在精度相同的情况下，可以节省大量试件；而在试件数一定的条件下，又能提高预测精度。还给出了一个对比实例。

关键词：升降法可靠性疲劳试验冲击试验工程材料

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Reduction and subsequent carburization of pre-oxidation magnetite pellets

第十届全国免疫学学术大会

作者： Da-Xiang Na He Huang ang yin Lu Wang Peking University Center for Human Disease Genomics

Objective:To characterize CTRP4 as an anti-obesity adipokine Methods:Bioinformatics analysis;Adipocyte differentiation;Diet-Induced Obesity;Real-time PCR;Western Blot Result:Bioinformatics analysis showed that the promoter region of the CTRP4 sequence contains potential PPARγbinding *** differentiation of stimulated pre-adipocytes was promoted after treatment with CTRP4 recombinant *** level of CTRP4 was increased in adipocytes after adenovirus-mediated overexpression of PPARγor treatment with the PPARγagonist *** high-fat diet treatment,the CTRP4 transgenic mice showed an obvious resistance to weight *** and insulin tolerance testing demonstrated that insulin resistance was ameliorated in the Tg *** analyses showed that fatty liver and chronic inflammation of the adipose tissue were *** addition,the pathways involved in insulin sensitivity and energy expenditure,namely the Akt and AMPK pathways,were activated by CTRP4,both in cells stimulated with recombinant CTRP4 protein and in the tissues of CTRP4 transgenic ***:CTRP4 functions as an adipokine that regulates adipogenesis and corrects energy ***,CTRP4 may play a predominant role in the regulation of metabolism.

关键词： CTRP4 adipokine PPARγ obesity adipogenesis inflammation

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Journal of Central South University 2022年第6期29卷 1856-1868页

作者： CHEN Suo CHEN Dong LYU Ya-nan WU Fei-bao yin Wei-ang School of Iron and Steel Soochow UniversitySuzhou 215131China Department of Mechanical and Electrical Engineering Suzhou Institute of Industrial TechnologySuzhou 215104China

Magnetite is a kind of iron ore that is difficult to *** order to improve the carburizing performance of magnetite pellet,pre-oxidation treatment was carried out,and the oxidation,reduction and carburization behaviors of magnetite pellet were investigated in this *** magnetite pellet was oxidized in the air and carburized in CO-CO_(2)-H_(2) gas mixtures,the oxidation,reduction and carburization behaviors were demonstrated by detecting phase change,microstructure,carburizing index via thermogravimetry,X-ray diffraction(XRD),infrared carbon-sulfur analyzer,and scanning electron microscope(SEM).The results show that the dense magnetite particles inside pellet are oxidized to porous hematite particles,and the Fe_(3)O_(4) transforms to Fe_(2)O_(3) with high lattice defect concentration during the pre-oxidation *** the porous hematite particles and newly formed Fe_(2)O_(3) significantly promote the reduction *** metallic iron particles are produced in the reduction ***,both high reduction efficiency and the porous structure of metallic iron particles dramatically enhance the carburization efficiency of *** preoxidation temperature favors to the carburization of magnetite ***,the carburized index decreases due to the recrystallization of iron oxide when the temperature extends to 1000℃.The optimum pre-oxidation temperature for magnetite pellet carburization is 900℃.

关键词： magnetite pre-oxidation carburization porous particle recrystallization

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多状态串并联系统结构与维修策略

航空学报 2016年第11期37卷 3395-3403页

作者：印明昂孙志礼王健张禹东北大学机械工程与自动化学院沈阳110004

为准确构建生产系统中系统结构与设备维修之间的关系,以串并联系统冗余分配问题(RAP)为基础,引入基于系统可靠性的机会维修策略与基于状态的检测间隔,建立了设备购置与维修费用最少为目标的系统结构与维修策略的联合模型,从而在保证系... 详细信息

为准确构建生产系统中系统结构与设备维修之间的关系,以串并联系统冗余分配问题(RAP)为基础,引入基于系统可靠性的机会维修策略与基于状态的检测间隔,建立了设备购置与维修费用最少为目标的系统结构与维修策略的联合模型,从而在保证系统生产效率和可用度的前提下,降低系统运行的总成本。利用半马尔可夫过程和通用生成函数(UGF)求解出系统在检测点上各状态的稳态概率、维修费用及可用度。通过算例表明,无论在系统设计之前还是在运行之后,将系统结构与维修策略综合考虑比分开考虑更具经济价值。

关键词：串并联系统基于状态的维修冗余分配问题通用生成函数马尔可夫过程