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Numerical Analysis of Steady Smoldering of Biomass Rods
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作者 Zhao Wentao Yu Guangxin +3 位作者 Zhang Yi Wang Youtang Zhou Dan He Fang 《燃烧科学与技术》 CAS CSCD 北大核心 2024年第5期507-519,共13页
Understanding the steady mechanism of biomass smoldering plays a great role in the utilization of smoldering technology.In this study numerical analysis of steady smoldering of biomass rods was performed.A two-dimensi... Understanding the steady mechanism of biomass smoldering plays a great role in the utilization of smoldering technology.In this study numerical analysis of steady smoldering of biomass rods was performed.A two-dimensional(2D)steady model taking into account both char oxidation and pyrolysis was developed on the basis of a calculated propagation velocity according to empirical correlation.The model was validated against the smoldering experiment of biomass rods under natural conditions,and the maximum error was smaller than 31%.Parameter sensitivity analysis found that propagation velocity decreases significantly while oxidation area and pyrolysis zone increase significantly with the increasing diameter of rod fuel. 展开更多
关键词 steady smoldering biomass rod numerical analysis 2D steady model sensitivity analysis
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First‑principles study on electronic structure,optical and magnetic properties of rare earth elements X(X=Sc,Y,La,Ce,Eu)doped with two‑dimensional GaSe
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作者 QIU Shenhao XIAO Qingquan +1 位作者 TANG Huazhu XIE Quan 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第11期2250-2258,共9页
The electronic structure,magnetic,and optical properties of two-dimensional(2D)GaSe doped with rare earth elements X(X=Sc,Y,La,Ce,Eu)were calculated using the first-principles plane wave method based on den-sity funct... The electronic structure,magnetic,and optical properties of two-dimensional(2D)GaSe doped with rare earth elements X(X=Sc,Y,La,Ce,Eu)were calculated using the first-principles plane wave method based on den-sity functional theory.The results show that intrinsic 2D GaSe is a p-type nonmagnetic semiconductor with an indi-rect bandgap of 2.6611 eV.The spin-up and spin-down channels of Sc-,Y-,and La-doped 2D GaSe are symmetric,they are non-magnetic semiconductors.The magnetic moments of Ce-and Eu-doped 2D GaSe are 0.908μ_(B)and 7.163μ_(B),which are magnetic semiconductors.Impurity energy levels appear in both spin-up and spin-down chan-nels of Eu-doped 2D GaSe,which enhances the probability of electron transition.Compared with intrinsic 2D GaSe,the static dielectric constant of the doped 2D GaSe increases,and the polarization ability is strengthened.The ab-sorption spectrum of the doped 2D GaSe shifts in the low-energy direction,and the red-shift phenomenon occurs,which extends the absorption spectral range.The optical reflection coefficient of the doped 2D GaSe is improved in the low energy region,and the improvement of Eu-doped 2D GaSe is the most obvious. 展开更多
关键词 first principle two-dimensional GaSe electronic structure magnetic property optical property
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Skin care efficacy study of recombinant humanized collagen based on in vitro level
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作者 Jian Wang Yuhui Fan +3 位作者 Danfeng Li Ningwen Cheng Ling Li Yufeng Yu 《日用化学工业(中英文)》 CAS 北大核心 2024年第9期1030-1038,共9页
Studying the skin care efficacy of recombinant humanized collagen based on in vitro level.The stability of the recombinant humanized collagen was first analyzed by treating at different temperatures,then its skincare ... Studying the skin care efficacy of recombinant humanized collagen based on in vitro level.The stability of the recombinant humanized collagen was first analyzed by treating at different temperatures,then its skincare efficacy based on in vitro level was evaluated by detecting the inhibition rate of elastase,the inhibition rate of collagenase,the protein content of type I collagen in human fibroblasts,the inhibition of reactive oxygen species(ROS)with human keratinocytes,and the effects of the recombinant humanized collagen on the expression of hyaluronic acid(HA),filaggrin(FLG)and transglutaminase 1(TGM1)in keratinocytes.The results showed that recombinant humanized collagen was able to maintain stability at temperatures below 70℃.With regard to its skincare efficacy,recombinant humanized collagen could inhibit elastase and collagenase activities and promote the increase of type I collagen content in human fibroblasts.It also showed good inhibition of ROS in keratinocytes in vitro and could increase the expression of HA,FLG,and TGM1 in keratinocytes.In short,the recombinant humanized collagen exhibited a favourable skin care effect in vitro level.This study proved that it has potential firming,anti-wrinkle,moisturizing,and repairing efficacy,and is a valuable cosmetic raw material. 展开更多
关键词 recombinant humanized collagen stability human fibroblast cell in vitro keratinocytes skin care efficacy
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淮河流域初始水权分配实践研究 被引量:2
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作者 詹同涛 李瑞杰 焦军 《水利水电技术》 CSCD 北大核心 2018年第9期64-70,共7页
建立水权管理制度是流域水资源管理的发展趋势,初始水权分配是实施水权管理的首要前提。通过建立子和谐度函数对基本用水保障、生态用水保障、尊重历史与现状、公平性、高效性、可持续发展、权利与义务相结合7项初始水权分配原则进行量... 建立水权管理制度是流域水资源管理的发展趋势,初始水权分配是实施水权管理的首要前提。通过建立子和谐度函数对基本用水保障、生态用水保障、尊重历史与现状、公平性、高效性、可持续发展、权利与义务相结合7项初始水权分配原则进行量化描述,耦合各子和谐度函数,构建多准则初始水权分配模型,通过快速和谐搜索算法求解系统和谐度最大的一组作为分配结果。多准则初始水权分配模型应用于淮河流域实践的结果表明,通过数学函数量化各分配原则,该模型物理意义明确,分配结果较为合理。通过引入入河污染物限排惩罚函数,该模型实现了水资源量维和质维的统一,并从时间维度上量化了可持续发展原则,聚集了多种分配模式的优点。 展开更多
关键词 初始水权分配 量维 质维 可持续发展 和谐状态函数 快速和谐搜索算法 淮河流域
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Rheological and mechanical properties of wood fiber-PP/PE blend composites 被引量:9
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作者 高华 宋永明 +2 位作者 王清文 韩振 张明丽 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第4期315-318,共4页
For evaluation of the rheological and mechanical properties of highly filled wood plastic composites (WPCs), polypropylene/polyethylene (PP/PE) blends were grafted with maleic anhydride (MAH) to enhance the inte... For evaluation of the rheological and mechanical properties of highly filled wood plastic composites (WPCs), polypropylene/polyethylene (PP/PE) blends were grafted with maleic anhydride (MAH) to enhance the interfacial adhesion between wood fiber and matrix. WPCs were prepared from wood fiber up to 60 wt.% and modified PP/PE was blended by extrusion. The rheological properties were studied by using dynamic measurement. According to the strain sweep test, the linear viscoelastic region of composites in the melt was determined. The result showed that the storage modulus was independent of the strain at low strain region (〈0.1%). The frequency sweep resuits indicated that all composites exhibited shear thinning behavior, and both the storage modulus and complex viscosity of MAH modified composites were decreased comparing to those unmodified. Flexural properties and impact strength of the prepared WPCs were measured according to the relevant standard specifications. The flexural and impact strength of the manufactured composites significantly increased and reached a maximum when MAH dosage was 1.0 wt%, whereas the flexural modulus after an initial decreased, also increased with MAH dosage. The increase in mechanical properties indicated that the presence of anhydride groups enhanced the interracial adhesion between wood fiber and PP/PE blends. 展开更多
关键词 wood fiber PP/PE blends COMPOSITES rheological properties mechanical properties
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Effects of Matrine on Adenine-Induced Chronic Tubulointerstitial Fibrosis in Rats 被引量:5
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作者 卢远航 常明向 邓安国 《Journal of Chinese Pharmaceutical Sciences》 CAS 2006年第1期59-65,共7页
Aim ,To study the mechanism relative to therapeutic effects of matrine on adenine-induced renal interstitial fibrosis in rats. Methods Sixty male Wistar rats were selected and randomly divided into 3 groups: normal c... Aim ,To study the mechanism relative to therapeutic effects of matrine on adenine-induced renal interstitial fibrosis in rats. Methods Sixty male Wistar rats were selected and randomly divided into 3 groups: normal control group (NCG) consisted of 8 rats, adenine treated group (ATG) 28 rats, and matrine treated group (MTG) 24 rats. Each rat in ATG and MTG was gavaged with adenine (250 mg·kg^-1·d^-1 ) for 21 d. After gavage with adenine for one week, each rat in MTG was administered intraperitoneally matrine(20 mg·kg^-1·d^-1 ) in vehicle ( 1 mL of 0.9% sodium chloride) daily. On days 14, 21, and 28, the serum levels of urea nitrogen, creatinine, and IL-6 were determined and the rat kidneys of ATG, MTG and NCGwere examined pathologically. Radioimmunoassay for serum IL- 6 immunohistochemical staining for TGF-β1 expression in the kidney and semiquantitative analysis were performed. HE staining for semiquantitative analysis of tubulointerstitial injury. Results The serum levels of urea nitrogen and creatinine in MTG were lower as compare to ATG ( P 〈 0.05 ) whereas serum IL- 6 and renal TGF-β1 expression levels were significantly lower than those in ATG (P 〈0.05 ), but all these indexes were higher than those in NCG (P 〈 0.01 ). In MTG, the index of tubulointerstitial lesion was lower than that in ATG (P 〈 0.05 ). Conclusion Matrine inhibits the renal tubulointerstial fibrosis in the adenine-induced rat model by suppressing serum level of IL-6 and expression of TGF-β1 in the tubulointerstitium. 展开更多
关键词 MATRINE ADENINE tubulointerstitial fibrosis transforming growth factor β1 INTERLEUKIN-6
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Dynamic Changes in Distribution of Lignin and Hemicelluloses in Cell Walls During Differentiation of Secondary Xylem in Eucommia ulmoides 被引量:5
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作者 贺新强 崔克明 李正理 《Acta Botanica Sinica》 CSCD 2001年第9期899-904,共6页
The dynamic changes in the distribution of lignin and hemicelluloses (xylans and xyloglucans) in cell walls during the differentiation of secondary xylem in Eucommia ulmoides Oliv. were studied by means of ultraviolet... The dynamic changes in the distribution of lignin and hemicelluloses (xylans and xyloglucans) in cell walls during the differentiation of secondary xylem in Eucommia ulmoides Oliv. were studied by means of ultraviolet light microscopy and transmission electron microscopy combined with immunogold labelling. In the cambial zone and cell expansion zone, xyloglucans were localized both in the tangential and radial walls, but no xylans or lignin were found in these regions. With the formation of secondary wall S-1 layer, lignin occurred in the cell corners and middle lamella, while xylans appeared in S-1 layer, and xyloglucans were localized in the primary walls and middle lamella. In pace with the formation of secondary wall S-2 and S-3 layer, lignification extended to S-1, S-2 and S-3 layer in sequence, showing a patchy style of lignin deposition. Concurrently, xylans distributed in the whole secondary walls and xyloglucans, on the other hand, still localized in the primary walls and middle lamella. The results indicated that along with the formation and lignification of the secondary wall, great changes had taken place in the cell walls. Different parts of cell walls, such as cell corners, middle lamella, primary walls and various layers of secondary walls, had different kinds of hemicelluloses, which formed various cell wall architecture combined with lignin and other cell wall components. 展开更多
关键词 cell wall LIGNIN hemicelluloses secondary xylem differentiation Eucommia ulmoides
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Comparison of hydroxyl radical-scavenging abilities between white rot fungus Lentinula edodes and five mildews on lignocellulose substance 被引量:1
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作者 张晓煜 黄慧艳 《Agricultural Science & Technology》 CAS 2006年第4期10-14,共5页
The hydroxyl radical(-OH)-scavenging ability of culture filtrates from submerged culture of Lentinula edodes AX3 and five mildews on lignocellulose substance was analysed. Only L. edodes AX3 showed significant -OH-s... The hydroxyl radical(-OH)-scavenging ability of culture filtrates from submerged culture of Lentinula edodes AX3 and five mildews on lignocellulose substance was analysed. Only L. edodes AX3 showed significant -OH-scavenging ability which reached 52.2% at about the 48th hour. All mildews could hardly scavenge -OH under the experimental conditions. -OH-scavenging ability is considered related to the mode and ability of lignocellulose degradation of a strain. The degradation or bioconversion products might be the substance base for.this effect. 展开更多
关键词 hydroxyl radical-scavenging Lentinula edodes MILDEW LIGNOCELLULOSE FILTRATE
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Genetic Diversity Analysis and Constructing Core Collection Based on Phenotypes in Cotton 被引量:1
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作者 贺道华 邢宏宜 +2 位作者 赵俊兴 李婷婷 赵艳宁 《Agricultural Science & Technology》 CAS 2010年第6期57-60,174,共5页
In that DNA diversity detected nowadays could not mean phenotypic diversity,it is the precondition of breeding project and basic research of crop improvement that genetic diversity analysis and sampling of core collec... In that DNA diversity detected nowadays could not mean phenotypic diversity,it is the precondition of breeding project and basic research of crop improvement that genetic diversity analysis and sampling of core collection by phenotypes.Phenotyping and statistic analysis on 9 traits of 92 accessions of cotton germplasm resource from three species(Gossypium hirsutum L.,Gossypium barbadence L.and Gossypium arboreum L.)were conducted.And the statistics(variation coefficient,proportion of special accessions and Shannon-Weaver information index)indicated that initial collection had abundant phenotypic diversity;software NTSYS-pc and the unweighted pair group method of arithmetic(UPGMA)were used for the cluster analysis on genetic similarity coefficient and genetic distance matrix,and the result showed that the genetic relationship among accessions was highly consistent with the pedigree;22 accessions of core collection were selected by software QGAStation,four statistics,such as variance difference percentage(VD%),mean difference percentage(MD%),coincidence rate(CR%)and variable rate(VR%),showed that the genetic diversity of core collection was approximately equal to the initial collection.The results of genetic diversity analysis based on phenotypic data and sampling of core collection would provide reference for breeding projects and basic research. 展开更多
关键词 COTTON Core collection Fiber quality Genetic diversity Germplasm resource
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Identification of Quantitative Trait Loci (QTLs) Affecting Yield and Fiber Properties in Chromosome 16 in Cotton Using Substitution Line 被引量:12
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作者 任立华 郭旺珍 张天真 《Acta Botanica Sinica》 CSCD 2002年第7期815-820,共6页
Gossypium hirsutum L. and G. barbadense L. are the two cultivated tetraploid species of cotton. The first is characterized by a high yield and wide adaptation, and the second by its super fiber property. Substit... Gossypium hirsutum L. and G. barbadense L. are the two cultivated tetraploid species of cotton. The first is characterized by a high yield and wide adaptation, and the second by its super fiber property. Substitution line in which a pair of intact chromosomes of TM_1 ( G. hirsutum ) were replaced by a pair of homozygous chromosomes of 3_79 ( G. barbadense ) is an excellent material for genetic research and molecular tagging. In this study, substitution line 16 (Sub 16) was used to evaluate the performance of the 16th chromosome in G. barbadense in TM_1 background. The genetic analysis using the major gene plus polygene mixed inheritance model in F 2∶3 family revealed that there might exist 2 QTLs respectively for boll size, lint percentage, lint index, fiber length and the first fruit branch node, 1 QTL for fiber elongation and flowering date, and no QTL for seed index, fiber strength and Micronaire in chromosome 16. However, 9 QTLs (LOD (logarithm of odds)≥3.0) controlling 6 quantitative traits were significantly identified in linkage group of chromosome 16 constructed in (TM_1×3_79) F 2by interval mapping. Among them, 1 QTL for boll size, fiber length, flowering date and fiber elongation could explain 15.2%, 19.7%, 12.1%, and 11.7% phenotypic variance respectively, 2 QTLs for lint index could explain 11.6% and 41.9%, and 3 QTLs for lint percentage could explain 8.7%, 9.6% and 29.2% phenotypic variance respectively. One unlinked SSR marker was associated with one QTL respectively for boll size and flowering date and they could explain 1.60% and 4.63% phenotypic variance. The traits associated significantly with chromosome 16 from Sub 16 were boll weight, lint percentage, lint index, fiber length, fiber elongation and flowering days. 展开更多
关键词 allotetraploid cotton substitution line chromosome 16 inheritance molecular marker QTL mapping
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Influence of Al Composition on Transport Properties of Two-Dimensional Electron Gas in Al_xGa_(1-x)N/GaN Heterostructures
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作者 唐宁 沈波 +7 位作者 王茂俊 杨志坚 徐科 张国义 桂永胜 朱博 郭少令 褚君浩 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第2期235-238,共4页
Magnetotransport properties of two-dimensional electron gases (2DEG) in AlxGa1-x N/GaN heterostructures with different Al compositions are investigated by magnetotransport measurements at low temperatures and in hig... Magnetotransport properties of two-dimensional electron gases (2DEG) in AlxGa1-x N/GaN heterostructures with different Al compositions are investigated by magnetotransport measurements at low temperatures and in high magnetic fields. It is found that heterostructures with a lower Al composition in the barrier have lower 2DEG concentration and higher 2DEG mobility. 展开更多
关键词 Alx Ga1-x N/GaN heterostructure two-dimensional electron gas transport property
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Fluctuation of Microfibrillar Protein Level in Lutoids of Primary Laticifers in Relation to the 67 kD Storage Protein in Hevea brasiliensis 被引量:1
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作者 田维敏 韩亚琴 +1 位作者 吴继林 胡正海 《Acta Botanica Sinica》 CSCD 2003年第2期127-130,共4页
Abundant microfibrillar protein inclusions were present in the lutoids of the primary laticifers in Hevea brasiliensis Mull. Arg. Two forms of the inclusions could be distinguished under the electron microscope, each ... Abundant microfibrillar protein inclusions were present in the lutoids of the primary laticifers in Hevea brasiliensis Mull. Arg. Two forms of the inclusions could be distinguished under the electron microscope, each in separate lutoids. As revealed by SDS-PAGE, the 59.5 kD and 63.5 kD proteins were the major components of the microfibrillar protein purified by isoeleettic point precipitation. Western-blotting analysis indicated that they were immunorelated with the 67 kD protein accumulated in the protein-storing cells. The 59.5 kD and 63.5 kD proteins were abundant in the uppermost part, the stem of new shoot and sustained their abundance during the growth and development of new shoot while their contents decreased remarkably in the lower parts of the trunk, accompanying by the accumulation of 3-5 kinds of proteins with low molecular weights. This fluctuating pattern suggested that the degradation of the 59.5 kD and 63.5 kD proteins had nothing to do with the new shoot growth and may be closely related to the primary laticifer differentiation. The 67 kD protein could not be detected in the young stem of new shoot when its leaves were broze-colored while the protein started to be accumulated in the stem, when the leaves of new shoot had matured, behaving like a typical vegetative storage protein. 展开更多
关键词 microfibrillar protein 67 kD protein shoot growth laticifer development Hevea brasiliensis
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Plant Proteomics in the Post-genomic Era 被引量:12
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作者 郭奕明 沈世华 +1 位作者 荆玉祥 匡廷云 《Acta Botanica Sinica》 CSCD 2002年第6期631-641,共11页
Proteomics is one of the most active research fields in the post-genomic era. Here we briefly introduce the scientific background of the origination of proteomics and its content, research method. The new developments... Proteomics is one of the most active research fields in the post-genomic era. Here we briefly introduce the scientific background of the origination of proteomics and its content, research method. The new developments of proteomics at the levels of individual plants, tissues, organs and organells, as well as its applications in the area of plant genetic diversity, mutant characterization, and plant physiology, etc are reviewed. At last, the challenge and prospect of proteomics are discussed. 展开更多
关键词 genome post-genome PROTEOME plant proteomics matrix-assisted laser-desorption/ionizationtime-of-flight mass spectrometry (MALDI-TOF/MS) two-dimensional polyacrylamide gel electrophoresis (2D-PAGE)
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Breeding of Transgenic Hybrid Cotton Variety‘Yumian 50' and Cultivation Technology
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作者 唐中杰 房卫平 +2 位作者 吕淑平 聂利红 谢德意 《Agricultural Science & Technology》 CAS 2017年第8期1399-1402,共4页
The mid-early-maturing new cotton variety 'Yumian 50' was bred by In-stitute of Industrial Crops, Henan Academy of Agricultural Sciences. It was exam-ined and approved by Henan Provincial Crop Variety Approval Commi... The mid-early-maturing new cotton variety 'Yumian 50' was bred by In-stitute of Industrial Crops, Henan Academy of Agricultural Sciences. It was exam-ined and approved by Henan Provincial Crop Variety Approval Committee in 2016 (Yushenmian 2016002). In order to study the variety characteristics of 'Yumian 50' and the key points of its cultivation technology and accelerate its application in cot-ton production, the breeding process of 'Yumian 50' was described in this paper. The test data of 26 times for 3 years of 'Yumian 50' participating in Henan region-al tests in 2012-2014 were summarized. The results showed that 'Yumian 50' had outstanding performance in Henan regional tests and production tests. 'Yumian 50' is a new cotton variety with characteristics of high yield, good quality and high re-sistance to diseases and pests. 展开更多
关键词 Transgenic Hybrid Cotton 'Yumian 50' YIELD Fiber Quality CultivationTechnoloav
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Correlations between Quality Index and Content of Cellulose and Lignin in Upper Leaves of Fluecured Tobacco in Wulin Mountain Area
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作者 刘晓冰 孟霖 +4 位作者 梁盟 王程栋 宋文静 郑家宝 徐宜民 《Agricultural Science & Technology》 CAS 2015年第10期2135-2140,2143,共7页
In order to study the correlations among quality indexes of tobacco leaf and contents of cellulose and lignin in upper leaves of flue-cured tobacco, 48 B2F flue-cured tobacco samples in seven counties of Wulin mountai... In order to study the correlations among quality indexes of tobacco leaf and contents of cellulose and lignin in upper leaves of flue-cured tobacco, 48 B2F flue-cured tobacco samples in seven counties of Wulin mountain area in 2011 and 2012 were used as test materials to measure the contents of cellulose and lignin in tobacco leaves and analyze the differences among varieties and between years. Meanwhile, correlations among contents of cellulose and lignin and appearance quality, physical characteristics, general chemical components and indexes of senso- ry quality were studied. The results showed that the contents of cellulose and lignin had no significant difference among years and varieties. Cellulose content was sig- nificantly correlated with some indexes of appearance qualities, physical indexes, general chemical compositions and sensory qualities. Lignin content was significantly correlated with grayness and oil content but not other quality indexes of tobacco leaf. It could be seen that the differences of cellulose and lignin contents between different years and among varieties were not significant. Cellulose content was closely correlated with quality indexes of tobacco leaf while lignin content had a small effect on tobacco leaf quality. 展开更多
关键词 Flue-cured tobacco Upper leaf CELLULOSE LIGNIN Correlation analysis
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Comparative Study on Muscle Fiber Characteristics and Muscle Nutritional Quality between Two Groups of Yellow River Carps 被引量:3
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作者 杨又兵 卞军平 +2 位作者 马秀英 王伟 曾珍珍 《Agricultural Science & Technology》 CAS 2017年第8期1432-1436,1483,共6页
The aim was to protect the Henan Yellow River carp germplasm resources and provide a scientific basis for the meat quality improvement of Yellow River carps. With artificially farmed and wild Henan Yellow River carps ... The aim was to protect the Henan Yellow River carp germplasm resources and provide a scientific basis for the meat quality improvement of Yellow River carps. With artificially farmed and wild Henan Yellow River carps as the research objects, comparative study on muscle fiber diameter and density, routine nutritional composition, calcium and phosphorus contents and amino acids composition was conducted between the two groups of carps. The results showed that the moisture content was significantly higher (P 〈0.05), the crude fat and crude protein contents were significantly lower (P〈0.05), the essential amino acids and total amino acids contents were lower (P〉0.05), the phosphorus content was higher (P 〉0.05), and the calcium content was lower (P〉0.05) in the wild group compared with those in the farming group. The analysis of muscle fiber characteristics showed that there were significant differences in the average muscle fiber diameter (P〈0.05) and muscle fiber density (P〈0.01) between the two groups of Henan Yellow River carps. 展开更多
关键词 Yellow River carp PROTEIN Amino acids NUTRIENTS Muscle fiber
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Analysis on the Production Advantages of USA Pima Extra Long Staple Cotton
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作者 田立文 徐志武 +7 位作者 郑子漂 宁新民 崔建平 朱斌 徐海江 郭仁松 林涛 刘志清 《Agricultural Science & Technology》 CAS 2017年第5期892-903,共12页
This paper defines the following advantages of ELS (Extra Long Staple) also known as Pima cotton planted in the United States: first, the only variety which is concentrated in the planting area with good soil moist... This paper defines the following advantages of ELS (Extra Long Staple) also known as Pima cotton planted in the United States: first, the only variety which is concentrated in the planting area with good soil moisture and fertilizer retention performances and abundant light and heat resources; second; advanced and practi- cal material equipment and technology; third; high yield and good quality, significant planting scale benefit; fourth, feasible and reliable modernized intensive farm man- agement mode with large-scale agricultural machinery operation; fifth, high-efficient social services and policy support system, as well as reasonable planting layout, good brand influence, synchronization of high yield and good quality with large-scale benefits. Although the production capability of Pima cotton in the United States is considered to be the largest and most powerful country in the world, compared with the ELS production in China, both have their own advantages and characteristics. Therefore, it is suggested that by using the ELS production experience ol the Unit- ed Stages for reference, China should make use of the modern breeding technJques to accelerate the modification of synthetic genetic features of ELS variety, try its best to breed the ELS variety which is suitable for mechanical plucking as soon as possible, actively develop new technology to simplify the whole cost saving cultiva- tion, reform ELS production organization, vigorously develop the social service sys- tem, and adjust and optimize the ELS industry support policies, so as to fundamen- tally improve the competitiveness of China's ELS in international market. 展开更多
关键词 ELS (Extra Long Staple) or Pima cotton Natural Ecology Planting lay-out and scale Fiber quality Material equipment
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Inhibition of all-trans retinoic acid on MDM2 gene expression in astrocytoma cell line SHG-44
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作者 曾义 杨忠 +1 位作者 龙晓东 游潮 《Neuroscience Bulletin》 SCIE CAS CSCD 2008年第5期297-304,共8页
Objective To investigate the impact of all-trans retinoic acid (ATRA) on MDM2 gene expression in astrocytoma cell line SHG-44, and to provide basic data for further research on the progression mechanism and gene the... Objective To investigate the impact of all-trans retinoic acid (ATRA) on MDM2 gene expression in astrocytoma cell line SHG-44, and to provide basic data for further research on the progression mechanism and gene therapy of human astrocytoma. Methods The differential expressions of MDM2 gene and protein in SHG-44 cells were detected by cDNA microarray and Western blot, respectively, before and after treatment of ATRA. The expressions of MDM2 protein in WHO grade Ⅱ and grade Ⅳ astrocytomas were determined by immunohistochemical streptavidin-peroxidase method. Some differentially expressed genes were selected randomly for Northern blot analysis. Results The intensity ratio of ATRA-treated to untreated SHG-44 cell was 0.37 in the cDNA microarray, suggesting that the expression of MDM2 gene was down-regulated in SHG-44 cells after treatment with ATRA. Some genes differentially expressed in the microarray were confirmed by Northern blot. Western blot demonstrated that the optical density ratios of MDM2 to β-actin in ATRA-treated and untreated SHG-44 were 14.02±0.35 and 21.40±0.58 (t = 24.728, P = 0.000), respectively, suggesting that the expression of MDM2 protein was inhibited in ATRA-treated SHG-44 cells. Moreover, the percentages of MDM2-positive protein were 24.00% (6/25) and 56.52% (13/23) (x^2 = 5.298, P = 0.021) in WHO grade Ⅱ and grade Ⅳ astrocytomas, respectively, suggesting that the expression of MDM2 protein may increase along with the elevation of astrocytoma malignancy. Conclusion ATRA can inhibit MDM2 gene expression in SHG-44 cells, and MDM2 is related to astrocytoma progression. 展开更多
关键词 all-trans retinoic acid ASTROCYTOMA SHG-44 cell line MDM2 cDNA microarray
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The algorithm of 3D multi-scale volumetric curvature and its application 被引量:13
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作者 陈学华 杨威 +2 位作者 贺振华 钟文丽 文晓涛 《Applied Geophysics》 SCIE CSCD 2012年第1期65-72,116,共9页
To fully extract and mine the multi-scale features of reservoirs and geologic structures in time/depth and space dimensions, a new 3D multi-scale volumetric curvature (MSVC) methodology is presented in this paper. W... To fully extract and mine the multi-scale features of reservoirs and geologic structures in time/depth and space dimensions, a new 3D multi-scale volumetric curvature (MSVC) methodology is presented in this paper. We also propose a fast algorithm for computing 3D volumetric curvature. In comparison to conventional volumetric curvature attributes, its main improvements and key algorithms introduce multi-frequency components expansion in time-frequency domain and the corresponding multi-scale adaptive differential operator in the wavenumber domain, into the volumetric curvature calculation. This methodology can simultaneously depict seismic multi-scale features in both time and space. Additionally, we use data fusion of volumetric curvatures at various scales to take full advantage of the geologic features and anomalies extracted by curvature measurements at different scales. The 3D MSVC can highlight geologic anomalies and reduce noise at the same time. Thus, it improves the interpretation efficiency of curvature attributes analysis. The 3D MSVC is applied to both land and marine 3D seismic data. The results demonstrate that it can indicate the spatial distribution of reservoirs, detect faults and fracture zones, and identify their multi-scale properties. 展开更多
关键词 3D multi-scale volumetric curvature adaptive differential operator in wavenumber domain multi-frequency expansion in time-frequency domain fault detection fracture zone data fusion
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Effects of P2Y_1 receptor on glial fibrillary acidic protein and glial cell line-derived neurotrophic factor production of astrocytes under ischemic condition and the related signaling pathways 被引量:3
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作者 孙景军 刘颖 叶诸榕 《Neuroscience Bulletin》 SCIE CAS CSCD 2008年第4期231-243,共13页
Objective The present study aimed to explore the role of P2Y1 receptor in glial fibrillary acidic protein (GFAP) production and glial cell line-derived neurotrophic factor (GDNF) secretion of astrocytes under isch... Objective The present study aimed to explore the role of P2Y1 receptor in glial fibrillary acidic protein (GFAP) production and glial cell line-derived neurotrophic factor (GDNF) secretion of astrocytes under ischemic insult and the related signaling pathways. Methods Using transient right middle cerebral artery occlusion (tMCAO) and oxygen-glucose-serum deprivation for 2 h as the model of ischemic injury in vivo and in vitro, immunofluorescence, quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR), Western blotting, enzyme linked immunosorbent assay (ELISA) were used to investigate location of P2Y1 receptor and GDNF, the expression of GFAP and GDNF, and the changes of signaling molecules. Results Blockage of P2Y1 receptor with the selective antagonist N^6-methyl-2′-deoxyadenosine 3′,5′-bisphosphate diammonium (MRS2179) reduced GFAP production and increased GDNF production in the antagonist group as compared with simple ischemic group both in vivo and in vitro. Oxygen-glucose-serum deprivation and blockage of P2Y1 receptor caused elevation of phosphorylated Akt and cAMP response element binding protein (CREB), and reduction of phosphorylated Janus kinase2 (JAK2) and signal transducer and activator of transcription3 (STAT3, Ser727). After blockage of P2Y1 receptor and deprivation of oxygen-glucose-serum, AG490 (inhibitor of JAK2) reduced phosphorylation of STAT3 (Ser727) as well as expression of GFAP; LY294002, an inhibitor of phosphatidylinositol 3-kinase (PI3-K), decreased phosphorylation of Akt and CREB; the inhibitor of mitogen-activated protein kinase kinase 1/2 (MEK 1/2) U0126, an important molecule of Ras/extracellular signal- regulated kinase (ERK) signaling pathway, decreased the phosphorylation of JAK2, STAT3 (Ser727), Akt and CREB. Conclusion These results suggest that P2Y1 receptor plays a role in the production of GFAP and GDNF in astrocytes under transient ischemic condition and the related signaling pathways may be JAK2/STAT3 and PI3-K/Akt/CREB, respectively, and that crosstalk probably exists between them. 展开更多
关键词 P2Y1 receptor GLIOSIS glial fibrillary acidic protein glial cell line-derived neurotrophic factor PI3-K/Akt/CREB JAK2/STAT3 Ras/ERK
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