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Bonding enhancement of cold rolling TA1 P-Ti/AA6061 composite plates via surface oxidation treatment
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作者 Lun FU Bin YANG +2 位作者 Yun-chang GUO Chao YU Hong XIAO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期2864-2880,共17页
TA1 P-Ti/AA6061 composite plate was produced by oxidizing the surface of the titanium plate and adopting a cold roll bonding process.The results revealed that the oxide film(Ti6O)prepared on the surface of TA1 pure ti... TA1 P-Ti/AA6061 composite plate was produced by oxidizing the surface of the titanium plate and adopting a cold roll bonding process.The results revealed that the oxide film(Ti6O)prepared on the surface of TA1 pure titanium was easy to crack during the cold roll bonding,thereby promoting the formation of an effective mechanical interlock at the interface,which can effectively reduce the minimum reduction rate of the composite plates produced by cold rolling of titanium and aluminium plates.Moreover,the composite plate subjected to oxidation treatment exhibited high shear strength,particularly at a 43%reduction rate,achieving a commendable value of 117 MPa.Based on oxidation treatment and different reduction rates,the annealed composite plates at temperatures of 400,450,and 500°C displayed favorable resistance to interface delamination,highlighting their remarkable strength-plasticity compatibility as evidenced by a maximum elongation of 31.845%. 展开更多
关键词 Ta1 P-Ti/AA6061 composite plate oxidation treatment annealing treatment cold roll bonding
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Degradation of corn stalk by the composite microbial system of MC1 被引量:39
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作者 GUO Peng WANG Xiaofen +3 位作者 ZHU Wanbin YANG Hongyan CHENG Xu CUI Zongjun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第1期109-114,共6页
The composite microbial system of MC1 was used to degrade corn stalk in order to determine properties of the degraded products as well as bacterial composition of MC1. Results indicated that the pH of the fermentation... The composite microbial system of MC1 was used to degrade corn stalk in order to determine properties of the degraded products as well as bacterial composition of MC1. Results indicated that the pH of the fermentation broth was typical of lignocellulose degradation by MC1, decreasing in the early phase and increasing in later stages of the degradation. The microbial biomass peaked on the day 3 after degradation. The MC1 efficiently degraded the corn stalk by nearly 70% during which its cellulose content decreased by 71.2%, hemicellulose by 76.5% and lignin by 24.6%. The content of water-soluble carbohydrates (WSC) in the fermentation broth increased progressively during the first three days, and decreased thereafter, suggesting an accumulation of WSC in the early phase of the degradation process. Total levels of various volatile products peaked in the third day after degradation, and 7 types of volatile products were detected in the fermentation broth. These were ethanol, acetic acid, 1,2-ethanediol, propanoic acid, butanoic acid, 3- methyl-butanoic acid and glycerine. Six major compounds were quantitatively analysed and the contents of each compound were ethanol (0.584 g/L), acetic acid (0.735 g/L), 1,2-ethanediol (0.772 g/L), propanoic acid (0.026 g/L), butanoic acid (0.018 g/L) and glycerine (4.203 g/L). Characterization of bacterial cells collected from the culture solution, based on 16S rDNA PCR-DGGE analysis of DNAs, showed that the composition of bacterial community in MC1 coincided basically with observations from previous studies. This indicated that the structure of MC1 is very stable during degradation of different lignocellulose materials. 展开更多
关键词 corn stalk cellulose degradation composite microbial system MC1
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Monthly composites from Sentinel-1 and Sentinel-2 images for regional major crop mapping with Google Earth Engine 被引量:13
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作者 LUO Chong LIU Huan-jun +3 位作者 LU Lii-ping LIU Zheng-rong KONG Fan-chang ZHANG Xin-le 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第7期1944-1957,共14页
Rapid and accurate access to large-scale,high-resolution crop-type distribution maps is important for agricultural management and sustainable agricultural development.Due to the limitations of remote sensing image qua... Rapid and accurate access to large-scale,high-resolution crop-type distribution maps is important for agricultural management and sustainable agricultural development.Due to the limitations of remote sensing image quality and data processing capabilities,large-scale crop classification is still challenging.This study aimed to map the distribution of crops in Heilongjiang Province using Google Earth Engine(GEE)and Sentinel-1 and Sentinel-2 images.We obtained Sentinel-1 and Sentinel-2 images from all the covered study areas in the critical period for crop growth in 2018(May to September),combined monthly composite images of reflectance bands,vegetation indices and polarization bands as input features,and then performed crop classification using a Random Forest(RF)classifier.The results show that the Sentinel-1 and Sentinel-2 monthly composite images combined with the RF classifier can accurately generate the crop distribution map of the study area,and the overall accuracy(OA)reached 89.75%.Through experiments,we also found that the classification performance using time-series images is significantly better than that using single-period images.Compared with the use of traditional bands only(i.e.,the visible and near-infrared bands),the addition of shortwave infrared bands can improve the accuracy of crop classification most significantly,followed by the addition of red-edge bands.Adding common vegetation indices and Sentinel-1 data to the crop classification improved the overall classification accuracy and the OA by 0.2 and 0.6%,respectively,compared to using only the Sentinel-2 reflectance bands.The analysis of timeliness revealed that when the July image is available,the increase in the accuracy of crop classification is the highest.When the Sentinel-1 and Sentinel-2 images for May,June,and July are available,an OA greater than 80%can be achieved.The results of this study are applicable to large-scale,high-resolution crop classification and provide key technologies for remote sensing-based crop classification in small-scale agricultural areas. 展开更多
关键词 Sentinel-1 Sentinel-2 monthly composites crop mapping Google Earth Engine
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Microstructure and thermal properties of recyclable Si_p/1199Al composites 被引量:4
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作者 修子扬 陈国钦 +2 位作者 杨文澍 宋美慧 武高辉 《中国有色金属学会会刊:英文版》 CSCD 2009年第6期1440-1443,共4页
Recyclable Sip/1199Al composites with high volume fraction of Si particles were fabricated by squeeze-casting method. The microstructure was observed and the thermal properties were tested and calculated by theoretica... Recyclable Sip/1199Al composites with high volume fraction of Si particles were fabricated by squeeze-casting method. The microstructure was observed and the thermal properties were tested and calculated by theoretical models.Sip/1199Al composites are all dense and macroscopically homogeneous without any particle clustering.The interface of Sip/1199Al is clean,smooth and free from any interfacial reaction products.Sip/1199Al composites have high thermal diffusivity(65.083 mm 2/s)and thermal conductivity (168.211 W/(m·℃)).The specific heat capacity of Sip/1199Al composites at constant pressure increases while the thermal diffusivity and thermal conductivity decrease with increasing temperature.Annealing treatment could improve the thermal properties.The results of Maxwell model and P.G.model are higher than those of experiment. 展开更多
关键词 复合材料 热性能 再生 热扩散率 制备方法 挤压铸造 体积分数 显微观察
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Fabrication and Performances of 1-3-2 Piezoelectric Ceramic/Polymer Composite 被引量:1
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作者 Likun Wang Guang Li +2 位作者 Hongliang Du Lei Qin Shuxiang Li 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期511-513,共3页
A novel 1-3-2 piezoelectric composite has been developed,which consists of piezoelectric ceramic plate and 1-3 piezoelectric composite.The composite was fabricated by dicing PZT ceramic along mutual perpendicular two ... A novel 1-3-2 piezoelectric composite has been developed,which consists of piezoelectric ceramic plate and 1-3 piezoelectric composite.The composite was fabricated by dicing PZT ceramic along mutual perpendicular two directions and then filling epoxy into grooves.The piezoelectric and electromechanical properties of the novel composite were determined. The results show a coefficient d_ (33) of 405pC/N,a vibration displacement of 113.5pm,an acoustic impendence of 13.3 Mraly, a bandwidth of 12kHz and a thickness electromechanical coupling coefficient of 0.56. 展开更多
关键词 1-3-2 piezoelectric composite FABRICATION PERFORMANCES
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The creep behavior of Mg-9Al-1Si-1SiC composite at elevated temperature 被引量:3
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作者 Pengwen Zhou Shaoxiong Zhang +6 位作者 Ming Li Hongxia Wang Weili Cheng Lifei Wang Hang Li Wei Liang Yiming Liu 《Journal of Magnesium and Alloys》 SCIE EI CAS 2020年第3期944-951,共8页
The creep properties of as-cast Mg-9Al-1Si alloy and Mg-9Al-1Si-1SiC composite were compared.The results show that Mg-9A1-lSi-lSiC composite performs a better creep resistance than that of Mg-9Al-1Si alloy at constant... The creep properties of as-cast Mg-9Al-1Si alloy and Mg-9Al-1Si-1SiC composite were compared.The results show that Mg-9A1-lSi-lSiC composite performs a better creep resistance than that of Mg-9Al-1Si alloy at constant temperature and stress(473 K,70MPa).Besides,the creep behavior of Mg-9Al-1 Si-1SiC composite at various temperature from 448 K to 498 K and under stresses of 70-90 MPa were systematically investigated.The Mg-9Al-1 Si-1SiC composite exhibited a stress exponent from 5.5 to 6.9 and the creep activation energy fell within the range of 86-111 kJ/mol.The results showed that the creep mechanism of Mg-9Al-1Si-1SiC composite was mainly attributed to the effects of secondary phase strengthening mechanism and dislocation climb mechanism. 展开更多
关键词 MICROSTRUCTURE Stress exponent n Creep activation energy Q Mg-9Al-1Si-1SiC composite
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Preparation of Composite Microporous Silica Membranes Using TEOS and 1,2-Bis(triethoxysilyl)ethane as Precursors for Gas Separation 被引量:2
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作者 漆虹 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第3期404-409,共6页
This paper reports on a new microporous composite silica membrane prepared via acid-catalyzed polymeric route of sol-gel method with tetraethylorthosilicate(TEOS)and a bridged silsesquioxane[1,2-bis(triethoxysilyl)eth... This paper reports on a new microporous composite silica membrane prepared via acid-catalyzed polymeric route of sol-gel method with tetraethylorthosilicate(TEOS)and a bridged silsesquioxane[1,2-bis(triethoxysilyl)ethane, BTESE]as precursors.A stable nano-sized composite silica sol with a mean volume size of^5 nm was synthesized. A 150 nm-thick defect-free composite silica membrane was deposited on disk support consisting of macroporous α-Al2O3 and mesoporousγ-Al2O3 intermediate layer by using dip-coating approach,followed by calcination under pure nitrogen atmosphere.The composite silica membranes exhibit molecular sieve properties for small gases like H2,CO2,O2,N2,CH4 and SF6 with hydrogen permeances in the range of(1-4)×10 -7mol·m -2·s -1·Pa -1(measured at 200°C,3.0×105 Pa).With respect to the membrane calcined at 500°C,it is found that the permselectivities of H 2 (0.289 nm)with respect to N2(0.365 nm),CH4(0.384 nm)and SF6(0.55 nm)are 22.9,42 and>1000,respectively, which are all much higher than the corresponding Knudsen values(H2/N2=3.7,H2/CH4=2.8,and H2/SF6=8.5). 展开更多
关键词 TETRAETHYLORTHOSILICATE 1 2-bis(triethoxysilyl)ethane composite silica membranes gas separation mo- lecular sieving
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Self-diffractionin Porous Silicon/PMMA-DR1 Composite Fil ms 被引量:1
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作者 JIA Zhen-hong 《Semiconductor Photonics and Technology》 CAS 2006年第1期18-20,42,共4页
Two-layer structure consisting of PS/PMMA-DR1 composite film planar waveguide layer on porous silicon cladding layer was fabricated in our experiment. The induced grating based on the third nonlinear optical propertie... Two-layer structure consisting of PS/PMMA-DR1 composite film planar waveguide layer on porous silicon cladding layer was fabricated in our experiment. The induced grating based on the third nonlinear optical properties was formed by interaction of two Nd∶YAG laser beams at 1064nm in the porous silicon/PMMA-DR1 waveguide. The diffraction efficiency of the first order diffracted light is measured to be about 0.2% of the total output. 展开更多
关键词 Porous Silicon PMMA-DR1 composite film SELF-DIFFRACTION Dynamic grating
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Composition Analysis and Identification of Ancient Glass Products Based on L1 Regularization Logistic Regression
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作者 Yuqiao Zhou Xinyang Xu Wenjing Ma 《Applied Mathematics》 2024年第1期51-64,共14页
In view of the composition analysis and identification of ancient glass products, L1 regularization, K-Means cluster analysis, elbow rule and other methods were comprehensively used to build logical regression, cluste... In view of the composition analysis and identification of ancient glass products, L1 regularization, K-Means cluster analysis, elbow rule and other methods were comprehensively used to build logical regression, cluster analysis, hyper-parameter test and other models, and SPSS, Python and other tools were used to obtain the classification rules of glass products under different fluxes, sub classification under different chemical compositions, hyper-parameter K value test and rationality analysis. Research can provide theoretical support for the protection and restoration of ancient glass relics. 展开更多
关键词 Glass composition L1 Regularization Logistic Regression Model K-Means Clustering Analysis Elbow Rule Parameter Verification
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Preparation and Properties of 1-octadecanol/1,3:2,4-di-(3,4-dimethyl) Benzylidene Sorbitol/Expanded Graphite Form-stable Composite Phase Change Material
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作者 XU Jun CHENG Xiaomin 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第3期728-735,共8页
A 1-octadecanol(OD)/1,3:2,4-di-(3,4-dimethyl) benzylidene sorbitol(DMDBS)/expander graphite(EG) composite was prepared as a form-stable phase change material(PCM) by vacuum melting method. The results of fie... A 1-octadecanol(OD)/1,3:2,4-di-(3,4-dimethyl) benzylidene sorbitol(DMDBS)/expander graphite(EG) composite was prepared as a form-stable phase change material(PCM) by vacuum melting method. The results of field emission-scanning electron microscopy(FE-SEM) showed that 1-octadecanol was restricted in the three-dimensional network formed by DMDBS and the honeycomb network formed by EG. X-ray diffraction(XRD) and Fourier transform infrared spectroscopy(FT-IR) results showed that no chemical reaction occurred among the components of composite PCM in the preparation process. The gel-to-sol transition temperature of the composite PCMs containing DMDBS was much higher than the melting point of pure 1-octadecanol. The improvements in preventing leakage and thermal stability limits were mainly attributed to the synergistic effect of the three-dimensional network formed by DMDBS and the honeycomb network formed by EG. Differential scanning calorimeter(DSC) was used to determine the latent heat and phase change temperature of the composite PCMs. During melting and freezing process the latent heat values of the PCM with the composition of 91% OD/3% DMDBS/6% EG were 214.9 and 185.9 kJ·kg-1, respectively. Its degree of supercooling was only 0.1 ℃. Thermal constant analyzer results showed that its thermal conductivity(κ) changed up to roughly 10 times over that of OD/DMDBS matrix. 展开更多
关键词 1-octadecanol 1 3 4-di-(3 4-dimethyl) benzylidene sorbitol expander graphite composite phase change materials synergistic effect GELATOR
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Electrochemical performance of La_(1-x)Sr_xCuO_(3-δ)-Sm_(0.15)Ce_(0.85)O_(1.925) composite cathodes in IT-SOFCs
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作者 ZHENG Minzhang XIN Hua LIU Xiaomei LIU Qian XU Dan SU Wenhui 《Rare Metals》 SCIE EI CAS CSCD 2006年第z1期256-260,共5页
The cathode material La1-xSrxCuO3-δ(x=0.15, 0.2, 0.3, 0.4) was synthesized by a sol-gel method. X-ray diffraction reveals that a single phase of perovskite is formed. The investigation of the electrical properties su... The cathode material La1-xSrxCuO3-δ(x=0.15, 0.2, 0.3, 0.4) was synthesized by a sol-gel method. X-ray diffraction reveals that a single phase of perovskite is formed. The investigation of the electrical properties suggests that La0.7Sr0.3CuO3-δ has the highest electrical conductivity. La0.7Sr0.3CuO3-δ powder was mixed with different amount SDC (Sm0.15Ce0.85O1.925) powder (5wt.%-30wt.%) as composite cathodes. Electrochemical properties of the composite cathodes were researched further. Investigation suggests that the addition of appropriate amount SDC to La0.7Sr0.3CuO3-δ can improve the electrochemical properties and obtain better cathodic performance. Using La0.7Sr0.3CuO3-δ-SDC composite materials as a cathode based on SDC electrolyte, higher current density and power density at intermediate temperatures can be obtained. 展开更多
关键词 SOFC composite Cathode La1-xSrxCuO3-δ SDC
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The fabrication and properties of 1-3 piezoelectric composite 被引量:2
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作者 QIU Yan-qin LIU Jun MENG Xian-feng CHEN Cai-feng YAN Ping LUO Ying 《材料科学与工程(中英文版)》 2008年第4期53-57,共5页
关键词 压电复合材料 制备 陶瓷纤维 性能 机械品质因数 陶瓷粉末 微观结构 环氧树脂
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Fabrication of GaN-Based Heterostructures with an InA1GaN/AlGaN Composite Barrier
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作者 全汝岱 张进成 +6 位作者 薛军帅 赵一 宁静 林志宇 张雅超 任泽阳 郝跃 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第8期127-130,共4页
CaN-based heterostructures with an InAlCaN/AlCaN composite barrier on sapphire (0001) substrates are grown by a low-pressure metal organic chemical vapor deposition system. Compositions of the InAiGaN layer are dete... CaN-based heterostructures with an InAlCaN/AlCaN composite barrier on sapphire (0001) substrates are grown by a low-pressure metal organic chemical vapor deposition system. Compositions of the InAiGaN layer are determined by x-ray photoelectron spectroscopy, structure and crystal quality of the heterostruetures are identified by high resolution x-ray diffraction, surface morphology of the samples are examined by an atomic force microscope, and Hall effect and capacitance-voltage measurements are performed at room temperature to evaluate the electrical properties of heterostructures. The Al/In ratio of the InAlGaN layer is 4.43, which indicates that the InAlCaN quaternary layer is nearly lattice-matched to the CaN channel. Capacitance-voltage results show that there is no parasitic channel formed between the InAIGaN layer and the AlCaN layer. Compared with the InAl- CaN/CaN heterostructure, the electrical properties of the InAlCaN/AlGaN/GaN heterostructure are improved obviously. Influences of the thickness of the AlGaN layer on the electrical properties of the heterostructures are studied. With the optimal thickness of the AlGaN layer to be 5 nm, the 2DEG mobility, sheet density and the sheet resistance of the sample is 1889.61 cm2/V.s, 1.44 × 10^13 cm-2 and as low as 201.1 Ω/sq, respectively. 展开更多
关键词 ALGAN in on as is Fabrication of GaN-Based Heterostructures with an Ina1GaN/AlGaN composite Barrier of with
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Optimization of dendritic TS-1/Silica micro–mesoporous composites for efficient hydrodesulfurization of dibenzothiophene and 4,6-dimethyldibenzothiophene
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作者 Cheng-Kun Xiao Yu-Tong Zou +6 位作者 Dong-Ze Li En-Hua Wang Ao-Cheng Wang Dao-Wei Gao Ai-Jun Duan Peng Zheng Xi-Long Wang 《Petroleum Science》 SCIE EI CAS CSCD 2023年第4期2521-2530,共10页
A novel composite material(TD)composed of TS-1 microcrystalline and dendritic mesoporous silica nanospheres(DMSNs)was successfully prepared.The TD composite material had open pore structure and large specific surface ... A novel composite material(TD)composed of TS-1 microcrystalline and dendritic mesoporous silica nanospheres(DMSNs)was successfully prepared.The TD composite material had open pore structure and large specific surface area,which was conducive to the mass transfer of reactants and products.The Ti element in TS-1 could be used as an electron assistant,and the spillover d-electrons were conducive to the improvement of the sulfidation and dispersion of MoS_(2),thereby forming more type II MoS_(2) active phases.The incorporation of Ti could bring more Brønsted(B)and Lewis(L)acid,which was conducive to the hydrogenation pathway(HYD)selectivity(41.2%)of dibenzothiophene(DBT)hydrodesulfurization(HDS)and isomerization(ISO)route selectivity(21.9%)of 4,6-dimethyldibenzothiophene(4,6-DMDBT)HDS,thus improve the HDS activity of DBT and 4,6-DMDBT.NiMo/TD-70(Aging temperature=70℃)had the best HDS activities of DBT(99.0%)and 4,6-DMDBT(93.7%)due to its large open pore structure,good acidity,suitable metal-support interaction(MSI)and perfect dispersion of the metallic active sites. 展开更多
关键词 Dendritic TS-1-DMSNs composites NiMo/TD catalysts Dibenzothiophene4 6-Dimethyldibenzothiophene HYDRODESULFURIZATION
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Degradation of Cry1Ab Protein Within Transgenic Bt Maize Tissue by Composite Microbial System of MC1
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作者 Meng Yao Gu Wan-rong +3 位作者 Ye Le-fu Chen Dong-sheng Li Jing Wei Shi 《Journal of Northeast Agricultural University(English Edition)》 CAS 2014年第4期10-17,共8页
Environmental safety issues involved in transgenic plants have become the concern of researchers, practitioners and policy makers in recent years. Potential differences between Bt maize(ND1324 and ND2353 expressing t... Environmental safety issues involved in transgenic plants have become the concern of researchers, practitioners and policy makers in recent years. Potential differences between Bt maize(ND1324 and ND2353 expressing the insecticidal Cry1Ab protein) and near-isogenic non-Bt varieties(ND1392 and ND223) in their influence on the composite microbial system of MC1 during the fermentation process were studied during 2011-2012. Cry1Ab protein in Bt maize residues didn't affect characteristics of lignocellulose degradation by MC1, pH of fermentation broth decreasing at initial stage and increasing at later stage of degradation. The quality of various volatile products in fermentation broth showed that no signifi cant difference of residues fermentation existed between Bt maize and non-Bt maize. During the fermentation MC1 efficiently degraded maize residues by 83%-88%, and cellulose, hemicelluloses and lignin content decreased by 70%-72%, 72%-75% and 30%-37%, respectively. Besides that, no consistent difference was found between Bt and non-Bt maize residues lignocellulose degradation by MC1 during the fermentation process. MC1 degraded 88%-89% Cry1Ab protein in Bt maize residues, and in the fermentation broth of MC1 and bacteria of MC1 Cry1Ab protein was not detected. DGGE profi le analyses revealed that the microbial community drastically changed during 1-3 days and became stable until the 9th day. Though the dominant strains at different fermentation stages had signifi cantly changed, no difference on the dominant strains was observed between Bt and non-Bt maize at different stages. Our study indicated that Cry1Ab protein did not infl uence the growth characteristic of MC1. 展开更多
关键词 Bt maize degradation of Cry1AB protein composite microbial system of MC1
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Photocatalytic Hydrogen Evolution from the Splitting of Water over Cd_(1-x)Zn_xS/K_2La_2Ti_3O_(10) Composites under Visible Light Irradiation
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作者 刘利 GUO Dongmei +2 位作者 崔文权 HU Jinshan 梁英华 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第5期928-934,共7页
A series of Cd1-xZnxS/K2La2Ti3O10 composites were synthesized via a simple co-precipitation method. The prepared samples were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), X-ray energy di... A series of Cd1-xZnxS/K2La2Ti3O10 composites were synthesized via a simple co-precipitation method. The prepared samples were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), X-ray energy dispersive spectroscopy(EDX), ultraviolet-visible diffuse reflection(UV-Vis), X-ray photoelectron spectroscopy(XPS) and photoluminescence(PL) measurements. The composite structures consisted of Cd1-xZnxS nanoparticles evenly distributed on the surface of K2La2Ti3O10. The absorption edge of K2La2Ti3O10 shifted to the visible light region upon introduction of the Cd1-xZnxS nanoparticles. The photocatalytic activities of the catalysts were evaluated by hydrogen production under visible light irradiation. The prepared Cd0.8Zn0.2S(30wt%)/K2La2Ti3O10 exhibited higher photocatalytic activity, evolving 6.92 mmol/g H2 under visible light irradiation for 3 h. The promoted photocatalytic activity of the composites was attributed to the synergistic effect between Cd1-xZnxS and K2La2Ti3O10, which resulted in enhanced separation of photogenerated electrons and holes. 展开更多
关键词 Cd1-xZnxS/K2La2Ti3O10 composites PHOTOCATALYSIS hydrogen evolution water splitting
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Structural and Optical Properties of Zn<sub>x-1</sub>Mg<sub>x</sub>O Ceramic Composites
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作者 Zayani Jaafar Othman Adel Matoussi 《Materials Sciences and Applications》 2012年第8期538-542,共5页
In the present work, we investigate the structural and optical properties of Znx-1MgxO composites prepared by the standard sintering method at 1200?C during 24 hours and doped with different percentages of magnesium x... In the present work, we investigate the structural and optical properties of Znx-1MgxO composites prepared by the standard sintering method at 1200?C during 24 hours and doped with different percentages of magnesium x between 0% and 40%. For this purpose, we have used the X-ray diffraction (XRD) and the atomic force microscopy (AFM) to study the effect of the magnesium’s proportion on the crystalline and morphology proprieties of the obtained samples. XRD analysis showed that all films are polycrystalline with a hexagonal wurtzite structure, with an orientation of the grains according to directions (0002) and (10-10). The AFM characterisation show that the degree of surface roughness (RMS) increases with the increasing of MgO content. Optical properties of the ceramics were investigated by Absorbance and Reflectance measurements at room temperature in the wavelength range 200 - 2400 nm. Optical band gap energies (Eg) were determined. Further cathodoluminescence and dielectric measurements would be carried out to study the influence of MgO doping on the dielectric and luminescent properties of the ZnMgO ceramics. 展开更多
关键词 Znx-1MgxO composites X-Ray DIFFRACTION AFM Optical Properties
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The Changes in World Oil Prices, Monetary Factors, and Foreign Index Toward Composite Index Movement: Indonesian Case for the Period of 2005-2011
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作者 Darmawan Achmad Ishak Ramli 《Journal of Modern Accounting and Auditing》 2013年第9期1263-1274,共12页
Capital market is one of the drivers of the economy through the formation of capital investor excess as well as an indicator of a country's economy. Movement of stock price index is often influenced by many factors, ... Capital market is one of the drivers of the economy through the formation of capital investor excess as well as an indicator of a country's economy. Movement of stock price index is often influenced by many factors, derived from the company's performance, monetary factor, and changes in world oil prices. This study highlights the problem in world oil prices due to political turmoil in the Middle East. The samples are taken from the Jakarta Composite Stock Price Index (JCI), oil prices, Indonesian inflation rate, Certificate of Bank Indonesia's (CBI) rate, and the reserve assets, during the period from January 2005 to December 2011 (84 months). Using the data published by the Bank of Indonesia, reports of the Central Bureau of Statistics (Biro Pusat Statistik, BPS), and other relevant sources, the data analyzed through the Eviews 7.1. The main objective of this study is to examine the effect of oil prices, foreign stock price index, and monetary variables (inflation rate, CBI rate, country's foreign reserves, and others) toward the JCI analyzed through the error correction model (ECM). Hypothesis testing with the F-test for the 95% confidence level indicates that the oil price, exchange rate (Indonesian Rupiah (IDR)/United States Dollar (USD)), CBI rate, foreign exchange reserves, the Dow Jones Index, and the Taiwan stock index, both simultaneously as well as partially have a significant influence on the JCI. 展开更多
关键词 Jakarta composite Stock Price Index 1CI) world oil prices country's foreign reserves IndonesianRupiah (IDR) foreign stock prices
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基质细胞衍生因子1修饰左旋聚乳酸多孔微球促进软骨细胞增殖和组织形成
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作者 马玥 檀诗雨 +4 位作者 楚飞洋 陈琢琦 刘思宇 刘文帅 刘霞 《中国组织工程研究》 CAS 北大核心 2025年第22期4653-4662,共10页
背景:二维培养条件下的软骨细胞增殖及表型维持受限,多孔微球作为支架材料可提供三维培养环境,以更好地模拟体内生长条件。基质细胞衍生因子1是有强趋化效力的稳态细胞因子,能够促进细胞的黏附与增殖。目的:明确接枝基质细胞衍生因子1... 背景:二维培养条件下的软骨细胞增殖及表型维持受限,多孔微球作为支架材料可提供三维培养环境,以更好地模拟体内生长条件。基质细胞衍生因子1是有强趋化效力的稳态细胞因子,能够促进细胞的黏附与增殖。目的:明确接枝基质细胞衍生因子1左旋聚乳酸多孔微球对软骨细胞生物学特性及软骨组织形成的影响。方法:(1)体外验证不同质量浓度基质细胞衍生因子1对兔软骨细胞增殖、迁移、表型维持的影响。(2)采用复乳法制备左旋聚乳酸多孔微球,利用碳二亚胺法将基质细胞衍生因子1接枝于左旋聚乳酸多孔微球上,通过酶联免疫吸附实验及孵育基质细胞衍生因子1特异荧光抗体验证接枝情况。(3)将兔软骨细胞分别接种于左旋聚乳酸多孔微球、接枝基质细胞衍生因子1左旋聚乳酸多孔微球上,检测细胞增殖与黏附。(4)在裸鼠背部皮下分别植入甲基丙烯酰胺基明胶-软骨细胞复合体(对照组)、左旋聚乳酸多孔微球-甲基丙烯酰胺基明胶-软骨细胞复合体(多孔微球组)、接枝基质细胞衍生因子1左旋聚乳酸多孔微球-甲基丙烯酰胺基明胶-软骨细胞复合体(多孔微球修饰组),8周后取材,分别进行组织学染色与成软骨相关基因qRT-PCR检测。结果与结论:(1)相较于0,1 000 ng/mL基质细胞衍生因子1,500 ng/mL基质细胞衍生因子1可促进软骨细胞的增殖与迁移,提升软骨细胞内Ⅱ型胶原、弹性蛋白、增殖细胞核抗原、Bcl-2 mRNA表达;(2)基质细胞衍生因子1成功接枝于左旋聚乳酸多孔微球上,接枝率为93.75%;(3)相较于左旋聚乳酸多孔微球,接枝基质细胞衍生因子1左旋聚乳酸多孔微球可促进软骨细胞的增殖、黏附;(4)裸鼠皮下植入8周后,相较于对照组、多孔微球组,多孔微球修饰组具有更明显的软骨陷窝结构、更丰富的软骨特异性基质和Ⅱ型胶原沉积,弹性蛋白、Ⅱ型胶原、增殖细胞核抗原、Bcl-2 mRNA表达升高。结果表明:接枝基质细胞衍生因子1左旋聚乳酸多孔微球有利于软骨细胞的黏附、增殖、表型维持以及体内软骨组织形成。 展开更多
关键词 左旋聚乳酸多孔微球 基质细胞衍生因子1 软骨细胞 细胞三维培养 组织工程软骨 复合支架
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HIF-1α、SIP1及MMP-9在甲状腺乳头状癌组织中的表达及意义 被引量:2
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作者 杨磊 唐萃 +2 位作者 王旎 杨俊艳 刘智敏 《免疫学杂志》 CAS CSCD 北大核心 2014年第10期897-901,共5页
目的探讨低氧诱导因子-1(HIF-1α)、Smad蛋白的相互作用蛋白1(SIP1)和基质金属蛋白酶-9(MMP-9)在甲状腺乳头状癌(PTC)中的表达及意义。方法采用免疫组化SP法检测72例人甲状腺乳头状癌和37例癌旁正常组织中HIF-1α、SIP1和MMP-9的表达水... 目的探讨低氧诱导因子-1(HIF-1α)、Smad蛋白的相互作用蛋白1(SIP1)和基质金属蛋白酶-9(MMP-9)在甲状腺乳头状癌(PTC)中的表达及意义。方法采用免疫组化SP法检测72例人甲状腺乳头状癌和37例癌旁正常组织中HIF-1α、SIP1和MMP-9的表达水平,分析其表达与临床病理指标的关系及三者间表达的相关性。结果在PTC组织中,HIF-1α、SIP1和MMP-9的阳性表达率分别为51.56%、51.39%和54.16%,显著高于癌旁正常组织(P<0.01)。HIF-1α、SIP1和MMP-9的表达与患者颈部淋巴结转移显著相关(P<0.05)。HIF-1α与SIP1、HIF-1α与MMP-9、SIP1和MMP-9的表达均呈显著正相关(rs=0.304,P=0.009;rs=0.243,P=0.040;rs=0.277,P=0.019)。2种蛋白(HIF-1α/SIP1,HIF-1α/MMP-9,SIP1/MMP-9)联合表达较二者之一表达与颈部淋巴结转移更具相关性(P<0.05)。HIF-1α、SIP1和MMP-9 3种蛋白联合表达较三者之一表达与颈部淋巴结转移更具有相关性(P<0.05)。结论 HIF-1α、SIP1和MMP-9在PTC组织中的表达与颈部淋巴结转移密切相关,且三者存在相互协同作用,其表达情况可能作为监测PTC颈部淋巴结转移的指标。 展开更多
关键词 甲状腺乳头状癌 HIF-1Α sip1 MMP-9
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