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Spatiotemporal variation of land surface temperature and its driving factors in Xinjiang,China

Journal of Arid Land 2024年第3期16卷 373-395页

作者： ZHANG Mingyu CAO Yu ZHANG Zhengyong ZHANG Xueying LIU Lin CHEN Hongjin GAO Yu YU Fengchen LIU Xinyi College of Sciences Shihezi UniversityShihezi 832000China Key Laboratory of Oasis Town and Mountain-Basin System Ecology Xinjiang Production and Construction CorpsShihezi 832000China yantai Institute of Coastal Zone Research Chinese Academy of SciencesYantai 264003China

Land surface temperature(LST) directly affects the energy balance of terrestrial surface systems and impacts regional resources, ecosystem evolution, and ecosystem structures. Xinjiang Uygur Autonomous Region is located at the arid Northwest China and is extremely sensitive to climate change. There is an urgent need to understand the distribution patterns of LST in this area and quantitatively measure the nature and intensity of the impacts of the major driving factors from a spatial perspective, as well as elucidate the formation mechanisms. In this study, we used the MOD11C3 LST product developed on the basis of Moderate Resolution Imaging Spectroradiometer(MODIS) to conduct regression analysis and determine the spatiotemporal variation and differentiation pattern of LST in Xinjiang from 2000 to 2020. We analyzed the driving mechanisms of spatial heterogeneity of LST in Xinjiang and the six geomorphic zones(the Altay Mountains, Junggar Basin, Tianshan Mountains, Tarim Basin, Turpan-Hami(Tuha) Basin, and Pakakuna Mountain Group) using geographical detector(Geodetector) and geographically weighted regression(GWR) models. The warming rate of LST in Xinjiang during the study period was 0.24℃/10a, and the spatial distribution pattern of LST had obvious topographic imprints, with 87.20% of the warming zone located in the Gobi desert and areas with frequent human activities, and the cooling zone mainly located in the mountainous areas. The seasonal LST in Xinjiang was at a cooling rate of 0.09℃/10a in autumn, and showed a warming trend in other seasons. Digital elevation model(DEM), latitude, wind speed, precipitation, normalized difference vegetation index(NDVI), and sunshine duration in the single-factor and interactive detections were the key factors driving the LST changes. The direction and intensity of each major driving factor on the spatial variations of LST in the study area were heterogeneous. The negative feedback effect of DEM on the spatial differentiation o

关键词： land surface temperature MOD11C3 climate change geographical detector(Geodetector) geographically weighted regression(GWR) source-sink effect Xinjiang

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IMMUNOMODULATING EFFECTS OF THE FUCOIDAN-GALACTOSAN SULFATE (F_12) ON MACROPHAGES IN MICE

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Chinese Journal of Reactive Polymers 2001年第1期10卷 73-76页

作者： ZHANG Guozhi YOU Xiaodong WANG Lei SONG Jianqiu WANG Hairen yantai kangtai medicine product corp. Shandong province 264006 College of Life Science Shandong UniversityJinan 250100

The immunomodulating effects of F12 on mouse peritoneal macrophages was intended to be studied with different doses of 20, 40, 80 and 120mg/Kg. F12 increased peroxidase activity in dexc dependent mammer from 0.02±0.001 to 0.175±0.038, 0.211±0.041, 0.137±0.045 and 0.078±0.036, respectively, increased cytotoxicity from 127.33±22.96 to 162.74±19.53, 237.30±25.15 , 178.62±36.22 and 158.66±42.75dpm, respectively, promoted phagocytic activity from 0.03±0.01 to0.21±0.016, 0.43±0.041, 0.40±0.032 and 0.30±0.160b. Furthermore, F12 in a concentration of 15, 30,60,120μg/ml enhanced IL-1 production from 0.15±0.02 to 0.20±0.005b 0.21±0.02,0.22±0.005,0.24±0.002 and 0.22±0.02,respectively. Thus F12 can be considered as an effective stimulator of macrophages.

关键词： Fucoidan-Galactosan sulfate Macrophage Tumor Cytotoxicity Interleukin-1.

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STUDIES ON THE ISOLATION PURIFICATION AND CHARACTERIZATION OF THE FUCOIDAN-GALACTOSAN SULFATE (FGS) FROM LAMINARIA JAPONICA

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Chinese Journal of Reactive Polymers 2000年第2期9卷 151-155页

作者： TANG Zhihong LI Fuchuan XU Zhongping WANG Hairen ZHANG Guozhi College of Life Science Shandong UniversityJinan 250100 yantai kangtai medicine product corp. Shandong province 264006

FGS, isolated from the water solution of enzymolyzed laminaria japonica, is a mixture of acid heteroglycans. Four fractions F1, F2, F3, and F4 were obtained from FGS by ion exchange chromatography. After further purified by gel filtration chromatography on a sepharose 2B and 6B column, we obtained F9, F10, F11, and F12. They showed single band when identified by electrophoresis. The molecular weight of F9, F10, F11, and F12 was estimated to be 216, 120, 138 and 140KD respectively. They containedа-glucosidic bond by IR and 1H-NMR analysis. The typical absorption peaks of these polysaccharides were showed in UV and IR spectra. These polysaccharides contained rha, fuc, man, gal, and uronate when identified by paper chromatography (p.c) and gas chromatography (GC). The molar ratio of these sugars was also assayed.

关键词： Laminaria japonica Fucoidan-Galactosan sulfate Isolation Purification Chromatograph(

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Design of process and control scheme for cyclohexanol production from cyclohexene using reactive distillation

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Chinese Journal of Chemical Engineering 2021年第12期34卷 96-105页

作者： Mingyuan Hu Hui Tian College of Chemistry and Chemical Engineering Yantai UniversityYantai 264005China Collaborative Innovation Center of Comprehensive Utilization of Light Hydrocarbon Resource Yantai UniversityYantai 264005China

Cyclohexanol is a commonly used organic ***,the most promising industrial process for synthesizing cyclohexanol,by cyclohexene hydration,suffers from a low conversion rate and difficult *** this paper,a three-column process for catalytic distillation applicable in the hydration of cyclohexene to cyclohexanol was established to solve *** with Aspen Plus shows that the process has good advantages,the conversion of cyclohexene reached 99.3%,and the product purity was>99.2%.The stable operation of the distillation system requires a good control *** design of the control scheme is very ***,at present,the reactive distillation process for cyclohexene hydration is under investigation experimentally and by steady-state ***,three different plant-wide control schemes were established(CS1,CS2,CS3) and the position of temperature sensitive stage was selected by using sensitivity analysis method and singular value decomposition *** Tyreus-Luyben empirical tuning method was used to tune the controller ***,Aspen Dynamics simulation software was used to evaluate the performance of the three control *** introducing ΔF±20% and χ_(ENE)±5%,comparison the changes in product purity and yield of the three different control *** comparison,we can see that the control scheme CS3 has the best performance.

关键词： Cyclohexene hydration Catalytic distillation Control schemes Dynamic Simulation

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Phytoplankton community dynamics during Alexandrium blooms in 2019 off the Qinhuangdao coast,Bohai Sea,China

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Journal of Oceanology and Limnology 2022年第6期40卷 2416-2429页

作者： Yixuan XIE Renye DING Daojun ZHA Yu LI Guowang YAN Yaya ZHANG Haiyan WU Guanchao ZHENG Zhijun TAN Tao JIANG School of Marine Technology and Geomaties Jiangsu Ocean UniversityLianyungang 222005China School of Ocean Yantai UniversityYantai 264005China Key Laboratory of Testing and Evaluation for Aquatic product Safety and Quality Ministry of Agriculture and Rural Aff airsYellow Sea Fisheries Research InstituteChinese Academy of Fishery SciencesQingdao 266071China

Alexandrium blooms in the northwest area of the Bohai Sea(Qinhuangdao coastal area),China,produce large amounts of toxins that could be enriched in shellfish and consequently harm human *** understand the succession of the phytoplankton community structure during Alexandrium bloom events in the northwest area of the Bohai Sea off Qinhuangdao from April 2 to May 7,2019,microscopy observations and high-performance chromatography(HPLC)-pigment analysis were *** species of phytoplankton were identified,mainly diatoms and dinofl *** abundance of Alexandrium reached the maximum on April 16(3.3×10^(3) cells/L).HPLC-pigment CHEMTAX analysis showed that the phytoplankton community was composed mainly of diatoms,dinofl agellates,prasinophytes,and *** were the main contributor to the total Chl-a *** was a downward trend for the proportion of diatom biomass to the total Chl-a pool,followed by an upward *** proportion of dinoflagellate biomass showed the opposite trend,whereas that of the prasinophyte biomass presented an obvious increasing ***,nutrients,and nutrient structures were the main factors on the distribution of different phytoplankton groups in the study area as shown in the redundancy *** work illustrates the succession of phytoplankton community structures during Alexandrium blooms and provided a theoretical basis for studies on the mechanism underlying the outbreak of harmful algal blooms in sea areas.

关键词： Alexandrium bloom phytoplankton population environmental factor high-performance chromatography(HPLC)-CHEMTAX phytoplankton pigment Qinhuangdao

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High Efficient Extraction of Phthalates in Aquatic products by a Modified QuEChERS Method

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Chemical Research in Chinese Universities 2013年第4期29卷 653-656页

作者： WANG Wen-wen GAO Fu-kai LI Gui-zhi LIU Zhen-bo LIU Yong-ming College of Chemistry and Chemical Engineering Yantai University Yantai 264005 P. R. China

A simple, environmentally friendly and high efficient extraction method was proposed for the determina- tion of five phthalates in aquatic products by gas chromatography combined with mass spectrometry detector （GC-MS）. When this method was adopted, samples were pretreated by modified QuEChERS（quick, easy, cheap, effective, rugged and safe） method. An environmentally friendly extractant（ethanol aqueous solution） replaced toxic acetonitrile for extracting phthalates in the protein-matrix samples. Fluorescence quenching spectra of bovine serum albumin（BSA） with phthalates show that there was a high-affinity interaction between phthalate and protein, de- creasing the extraction efficiency of phthalates from fish samples. However, in the 80%（volume fraction, ~） ethanol aqueous solution, a slow but full protein denaturation takes place, which would cause the unfolding of protein and the release of phthalates. Meanwhile, the fat-soluble impurities are extracted less in ^（ethanol） 80% aqueous solution than in either ~p（ethanol） 100% or hydrophobic solvents in the liquid-liquid extraction procedure. Therefore the puri- fication steps were greatly simplified. Overall recoveries were 81.77%--90.5% with limits of detection between 2.53 and 9.61 ~tg/L, and relative standard deviation values at 1.15%---4.85%. The proposed approach was satisfactorily applied to the determination of phthalates in real aquatic products, such as fish, shrimp and oyster.

关键词： Phthalate Modified quick, easy, cheap, effective, rugged and safe(QuEChERS) method Protein Aquatic product Gas chromatography-mass spectrometry-selected ion monitoring(GC-MS-SIM)

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Microstructural Evolution of Ti-5.6Al-4.8Sn-2Zr-1Mo-0.35Si-0.7Nd Titanium Alloy with Carbon Additions

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Journal of Materials Science & Technology 2006年第5期22卷 616-620页

作者： Shangzhou ZHANG Yuan GAO Ziquan LIU Yuyin LIU Rui YANG School of Environment and Materials Engineering Yantai University Yantai 264005 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The effect of carbon addition on microstructural evolution was studied in a near-α titanium alloy （Ti-5.6Al- 4.8Sn-2Zr-1Mo-0.35Si-0.7Nd）. It was found that flake and ribbon titanium carbides with a NaCl crystal structure formed in the as-cast alloys with carbon additions of over 0.17 wt pct. Flake carbide particles are the product of eutectic transformation and precipitate from the high-temperature β phase. The ribbon carbide particles are primary phases formed prior to the nucleation of any metallic phases. The as-cast alloys with carbide precipitation after heat-treatment at βt-30℃ followed by water quenching showed the spheroidization of α lamellae and partial dissolution of carbide particles. After annealing at βt＋15℃, carbide particles are mostly distributed at the grain boundary and spheroidized through mixed grain boundary plus bulk diffusions.

关键词： Titanium alloy Carbon Microstructure Heat treatment Carbide

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Form factors for B meson weak decays in QCD light cone sum rules with a chiral current correlator

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Chinese Science Bulletin 2014年第29期59卷 3771-3786页

作者： Zuo-Hong Li Department of Physics Yantai University

We report some applications of QCD light cone sum rules(LCSR)to B meson weak *** emphasis is on estimates of the form factors for B decays into a pseudoscalar(P)/vector(V)meson,with a certain chiral current *** main new ingredient,as compared with the case of the standard correlators,is that in the operator product expansion calculations,the contributions due to the twist-3 distribution amplitudes of the related light mesons,which are less known and would bring a larger uncertainty to the calculations with the standard correlators,cancel out fully in the B!P case and do out partially in the B!V *** important observation,which is similar to that in soft collinear effective theory,is made in twist-3 approximation:whereas only one independent form factor is needed for parameterizing the hadronic matrix elements for a B!P transition induced by all the relevant heavy-light quark currents,there exist two independent form factors under the condition of neglecting the terms suppressed by a factor of m2V,for the B!V ***,the improved LCSR approach could be of stronger predictive power for the weak form ***,this approach is employed to understand the B!D transitions by introducing a leading twist-2 DA for an energetic D meson,combined with some of other QCDbased approaches.A detailed QCD next-to-leading order calculation of the B!p form factors is presented for an illustrative purpose,and the sum rule results are used to extract the Cabibbo–Kobayashi–Maskawa matrix element jVubj from the latest BaBar data.

关键词： B介子衰变求和规则 QCD 外形电流手性光锥矩阵元素

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The regular representation and regular covariant representation of crossed products of Woronowicz C^(*)-algebras

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Science China Mathematics 2005年第9期48卷 1245-1259页

作者： ZHANG Xiaoxia~(1,2) & GUO Maozheng~(1,3) 1. School of Mathematical Sciences,Peking University,Beijing 100871,China 2. Department of Mathematics,yantai University,yantai 264005,China 3. LMAM,Peking University,Beijing 100871,China School of Mathematical Sciences Peking University Beijing China Department of Mathematics Yantai University Yantai China LMAM Peking University Beijing China

In this paper,it is shown that the regular representation and regular covariant representation of the crossed products A×α G correspond to the twisted multiplicative unitary operators,where A is a Woronowicz C~*-algebra acted upon by a discrete group ***,it is also shown that the regular covariant C~*-algebra is the Woronowicz C~*-algebra which corresponds to a multiplicative ***,an explicit description of the multiplicative unitary operator for C(SU_q(2) )×α (?) is given in terms of those of the Woronowicz C~*-algebra C(SU_q(2) ) and the discrete group G.

关键词： multiplicative unitary operator, Woronowicz C*-algebra, crossed product.

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Theoretical Study of the Stereodynamics of the Reaction C(^(3)P)+CH(X^(2)Π) and Its Isotopic Variants

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Chinese Physics Letters 2011年第6期28卷 106-109页

作者： WU Ji-Cheng WANG Mei-Shan YANG Chuan-Lu LI Xiao-Hu CHEN Xiao-Qiong School of Physics Ludong UniversityYantai 264025

Vector correlations between products and reagents of the reaction C+CH and the isotopic variant reactions are calculated by employing the quasi-classical trajectory method based on the adiabatically 1^(2)A" double−many-body-expansion potential-energy surface computed and numerically fitted by Boggio-Pasqua et *** normalized polarization-dependent differential cross-sections and the distributions of P(θr),P(φr)and P(θr,φr)at the selected collision energy are discussed in *** values of the product rotational alignment parameter{P_(2)(j'⋅k)}are also calculated and plotted as functions of the collision energy in the range 0.005–0.5 *** computed results show that the rotational polarizations of the product present pronounced different characters as the mass substituted atom increasing.

关键词： rotational collision substituted

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