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单位分数代数和的可表性 被引量:2
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作者 张水胜 堵秀凤 崔继贤 《高师理科学刊》 2004年第3期14-15,共2页
给出了单位分数代数和的可表性定理及其推论
关键词 单位分数 互素 可表性
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命题逻辑中的可表性 被引量:1
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作者 苏岐芳 苏雅春 《松辽学刊(自然科学版)》 1997年第4期89-92,共4页
本文给出了可表性概念.应用可表性,处理了命题逻辑符号间的关系.
关键词 可表性 命题逻辑 功能完备集
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Biocorrosion property and cytocompatibility of calcium phosphate coated Mg alloy 被引量:6
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作者 徐丽萍 张二林 杨珂 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第8期2014-2020,共7页
Calcium phosphate coated Mg alloy was prepared. The phase constitute and surface morphology were identified and observed by X-ray diffractometer (XRD) and SEM. The results show that the coating is composed of flake-... Calcium phosphate coated Mg alloy was prepared. The phase constitute and surface morphology were identified and observed by X-ray diffractometer (XRD) and SEM. The results show that the coating is composed of flake-like CaHPO4-2H2O crystals. The corrosion resistance of the coated Mg alloy was measured by electrochemical polarization and immersion test in comparison with uncoated Mg alloy. Cytocompatibility was designed by observing the attachment, growth and proliferation of L929 cell on both coated and uncoated Mg alloy samples. The results display that the corrosion resistance of the coated Mg alloy is better than that of uncoated one. The immersion test also shows that the calcium phosphate coating can mitigate the corrosion of Mg alloy substrate, and tends to transform into hydroxyapatite (HA). Compared with uncoated Mg alloy, L929 cells exhibit good adherence, growth and proliferation characteristics on the coated Mg alloy, indicating that the cytocompatibility is significantly improved with the calcium phosphate coating. 展开更多
关键词 biodegradable Mg surface modification corrosion CYTOCOMPATIBILITY
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Phenotypic Plasticity in Response to the Heterogeneous Water Supplyin the Rhizomatous Grass Species, Calamagrostis epigejosin the Mu Us Sandy Land of China 被引量:4
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作者 张称意 于飞海 +1 位作者 陈玉福 董鸣 《Acta Botanica Sinica》 CSCD 2003年第10期1210-1217,共8页
Calamagrostis epigejos (L.) Roth. is a perennial grass with slender and long rhizome segments between interconnected neighbor ramets. To investigate the phenotypic plasticity in response to the heterogeneous soil wate... Calamagrostis epigejos (L.) Roth. is a perennial grass with slender and long rhizome segments between interconnected neighbor ramets. To investigate the phenotypic plasticity in response to the heterogeneous soil water supply, ramet pairs of the species were subjected to heterogeneous water supply by which either mother ramets or daughter ramets were in high or low soil water supply, respectively, in the Maowusu (Mu Us) Sandy Land of Nei Mongol. The results showed that the phenotypic characteristics of the individual ramets of C epigejos were greatly influenced by the heterogeneous water supply. The ramets treated with high water supply significantly produced more new rhizomes and more offspring (ramets), and accumulated more shoot biomass, and allocated more biomass to their shoots than those treated with low water supply. In comparison with the daughter ramets in homogeneous soil water supply, phenotypic characteristics, in terms of new rhizome growth, the production of new offspring, and the biomass allocation pattern, of the daughter ramets within the pairs of the species were not significantly changed, no matter that high or low soil water supply to mother ramets. The phenotypic responses of mother ramets to soil water supply were similar to those of daughter ramets. From these results, it is inferred that the interconnected ramets of C epigejos response phenotypically to their local soil water rather than to the soil water experienced by the interconnected ramets. The interconnected ramets of C epigejos might be independent of each other in water relationship, although they are physically interconnected with rhizome segments. The physiological independence of interconnected ramets might facilitate the risk spreading and thus enhance the genet survivorship under the frequent drought stresses in Mu Us Sandland. 展开更多
关键词 phenotypic plasticity heterogeneous soil water Calamagrostis epikejos ramet pairs RHIZOME clonal plants Maowusu (Mu Us) Sandy Land
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Elementary study of differential expression of total soluble proteins in different life phases of Porphyra yezoensis
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作者 孟春晓 高政权 +2 位作者 王依涛 罗韬 叶乃好 《Marine Science Bulletin》 CAS 2010年第2期32-37,共6页
Total soluble proteins of different life stages, filamentous sporophytes cultivated in high temperatures, and blade gametophytes harvested in different seasons, were identified by SDS-PAGE. The types and amounts of ex... Total soluble proteins of different life stages, filamentous sporophytes cultivated in high temperatures, and blade gametophytes harvested in different seasons, were identified by SDS-PAGE. The types and amounts of expressed proteins also varied amongst the samples. The fewest soluble proteins were present in filamentous sporophytes. There were more types and amounts of soluble protein in conchospores than in filamentous sporophytes, but fewer than in bulgy sporophytes. More types of protein were detected in filamentous sporophytes cultivated in high temperatures than in those growing in normal situations. The most types and amounts of protein were found in blade gametophytes in all samples. Blade gametophytes harvested last year and stored at -20 ℃ showed only minor differences in expression of proteins when compared with those harvested in different seasons. 展开更多
关键词 Porphyra yezoensis total soluble proteins differential expression
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Surfactant-assisted hydrothermally synthesized MoS_2 samples with controllable morphologies and structures for anthracene hydrogenation 被引量:9
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作者 李敏 王冬娥 +5 位作者 李佳鹤 潘振栋 马怀军 姜玉霞 田志坚 陆安慧 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第3期597-606,共10页
MoS_2 samples with controllable morphologies and structures were synthesized using surfactantassisted hydrothermal processes.The effects of surfactants(PEG,PVP,P123,SDS,AOT,and CTAB)on the morphologies and structure... MoS_2 samples with controllable morphologies and structures were synthesized using surfactantassisted hydrothermal processes.The effects of surfactants(PEG,PVP,P123,SDS,AOT,and CTAB)on the morphologies and structures of MoS_2 samples were investigated.The results revealed that spherical,bulk-like,and flower-like MoS_2 particles assembled by NH4~+-intercalated MoS_2 nano-sheets were synthesized.The morphologies of the MoS_2 samples and their structures(including the slab length and the number of stacked layers) of MoS_2 nano-sheets in these samples could be controlled by adjusting the surfactants.Mono-dispersed spherical MoS_2 particles could be synthesized with PEG via the creation of MoS_2 nano-sheets with slab lengths shorter than 15 nm and fewer than six stacked layers.Possible formation mechanisms of these MoS_2 samples created via surfactant-assisted hydrothermal processes are proposed.Further,the catalytic activities of MoS_2 samples for anthracene hydrogenation were evaluated in a slurry-bed reactor.The catalyst synthesized with the surfactant PEG exhibited the highest catalytic hydrogenation activity.Compared with the other catalysts,it had a smaller particle size,mono-dispersed spherical morphology,shorter slab length,and fewer stacked layers;these were all beneficial to exposing its active edges.This work provides an efficient approach to synthesize transition metal sulfides with controllable morphologies and structures. 展开更多
关键词 Molybdenum sulfide Surfactant-assisted Controllable morphology Mono-dispersed Active edges Anthracene hydrogenation
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AN ADAPTIVELY TRAINED KERNEL-BASED NONLINEAR REPRESENTOR FOR HANDWRITTEN DIGIT CLASSIFICATION 被引量:12
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作者 Liu Benyong Zhang Jing 《Journal of Electronics(China)》 2006年第3期379-383,共5页
In practice, retraining a trained classifier is necessary when novel data become available. This paper adopts an incremental learning procedure to adaptively train a Kernel-based Nonlinear Representor (KNR), a recentl... In practice, retraining a trained classifier is necessary when novel data become available. This paper adopts an incremental learning procedure to adaptively train a Kernel-based Nonlinear Representor (KNR), a recently presented nonlinear classifier for optimal pattern representation, so that its generalization ability may be evaluated in time-variant situation and a sparser representation is obtained for computationally intensive tasks. The addressed techniques are applied to handwritten digit classification to illustrate the feasibility for pattern recognition. 展开更多
关键词 Pattern recognition Handwritten digit recognition Incremental learning Sparse representation Kernel-based Nonlinear Representor (KNR)
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Expression and identification of recombinant soluble single-chain variable fragment of monoclonal antibody MC3 被引量:13
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作者 Feng-Tian He Rong-Fen Li Yun-Sheng Kang Yan Zhang,Department of Biochemistry & Molecular Biology,Third Military Medical University,Chongqing 400038,China Yong-Zhan Nie Bao-Jun Chen Tai-Dong Qiao Dai-Ming Fan,Institute of Digestive Disease,Xijing Hospital,Fourth Military Medical University,Xi’an 710032,Shaanxi Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第2期258-262,共5页
AIM: To generate soluble single chain variable fragments (ScFv) of monoclonal antibody MC3 recognizing colorectal and gastric carcinomas. METHODS: mRNA was isolated from the hybridoma cell line producing MC3 and the D... AIM: To generate soluble single chain variable fragments (ScFv) of monoclonal antibody MC3 recognizing colorectal and gastric carcinomas. METHODS: mRNA was isolated from the hybridoma cell line producing MC3 and the DNAs encoding variable domains of heavy and light chains (VH and VL) of the antibody were amplified separately by RT-PCR and assembled into ScFv DNA with a linker DNA. The ScFv DNA was ligated into the phagemid vector pCANTAB5E and the ligated sample was transformed into E.coli TG1.The transformed cells were infected with M13KO7 helper phage to yield recombinant phages. After two rounds of panning with gastric carcinoma cell line AGS highly expressing MC3-binding antigen, the phage clones displaying ScFv fragments of the antibody were selected by ELISA. 4 phage clones showing strong signal in ELISA were used to infect E.coli HB2151 to express soluble ScFvs. The soluble ScFvs were identified by Dot blot and Western blot, and their antigen-binding activity was assayed by ELISA. The VH and VL DNAs of the ScFv DNA derived from phage clone 19 were sequenced. RESULTS: The VH,VL and ScFv DNAs were about 340 bp, 320 bp and 750 bp respectively. After two rounds of panning to the recombinant phages, 18 antigen-positive phage clones were selected from 30 preselected phage clones by ELISA. All the soluble ScFvs derived from the 4 out of the 18 antigen-positive phage clones were about M(r)32000 and concentrated in periplasmatic space under the given culture condition. The soluble ScFvs could bind the antigen, and they shared the same binding site with MC3. The sequences of the VH and VL DNAs of the MC3 ScFv showed that the variable antibody genes belonged to the IgG1 subgroup,kappa-type. CONCLUSION: The soluble ScFv of MC3 is successfully produced, which not only provides a possible novel targeting vehicle for in vivo and in vitro study on associated cancers, but also offers the antibody a stable genetic source. 展开更多
关键词 Animals Antibodies Monoclonal Base Sequence Carcinoma Colorectal Neoplasms Enzyme-Linked Immunosorbent Assay Humans Immunoglobulin Fragments Immunoglobulin Variable Region Mice Molecular Sequence Data Recombinant Proteins Stomach Neoplasms Tumor Cells Cultured
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Relationship between process mineralogical characterization and beneficiability of low-grade laterite nickel ore 被引量:5
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作者 XU Peng-yun WANG Qiang +4 位作者 LI Chuang YU Qi FANG Hao SU Jian-fang GUO Xue-yi 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第10期3061-3073,共13页
Process mineralogy of low-grade laterite nickel ore in Indonesia was systematically characterized and the beneficiation process of mineral components such as limonite,serpentine and chromite was studied on the basis o... Process mineralogy of low-grade laterite nickel ore in Indonesia was systematically characterized and the beneficiation process of mineral components such as limonite,serpentine and chromite was studied on the basis of process mineralogy.The results show that the low-grade laterite nickel ore is a typical weathering sedimentary metamorphic oxidized ore,with the main valuable elements of Ni,Co and Cr and the main mineral components of limonite,serpentine,chromite,etc.There is no independent carrier mineral of Ni and Co in the raw ore,and the occurrence states of Ni and Co are relatively dispersed.For the limonite in laterite nickel mine,the nickel bearing magnetite concentrate with nickel grade of 1.98%and recovery rate of 88.42%can be obtained by reduction roasting magnetic separation process.For the serpentine in laterite nickel mine,the cobalt bearing concentrate with Co grade of 0.17%and recovery rate of 23.17%can be obtained by positive and reverse flotation process.A chromium concentrate containing 35.17%Cr_(2)O_(3) and a recovery of 33.42%can be obtained by using the combined process of coarse and fine classification and gravity and magnetic. 展开更多
关键词 laterite nickel ore low grade process mineralogy CHARACTERIZATION beneficiability
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Soluble Expression and Rapid Quantification of GFP-hepA Fusion Protein in Recombinant Escherichia coli 被引量:7
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作者 陈银 邢新会 +1 位作者 叶逢春 况莹 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第1期122-126,共5页
To establish a rapid quantification method for heparinase I during its production in recombinant Escherichia coli, a translational fusion vector was constructed by fusing the N terminus of heparinase I to the C termin... To establish a rapid quantification method for heparinase I during its production in recombinant Escherichia coli, a translational fusion vector was constructed by fusing the N terminus of heparinase I to the C terminus of a green fluorescent protein mutant (GFPmutl). As a result, not only was the functional recombinant expression of heparinase I in E. coli accomplished, but also a linear correlation was obtained between the GFP fluorescence intensity and heparinase I activity, allowing enzyme activity to be quantified rapidly during the fermentation. 展开更多
关键词 functional expression fusion protein green fluorescent protein (GFP) heparinase I rapid quantification
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ELEVATED SOLUBLE EPIDERMAL GROWTH FACTOR RECEPTOR LEVEL IN PITUITARY ADENOMA AND CARCINOMA 被引量:4
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作者 Yan-guoKong Zu-yuanRen Chang-baoSu Ren-zhiWang Wen-bingMa WeiLian 《Chinese Medical Sciences Journal》 CAS CSCD 2004年第3期199-202,共4页
To investigate effect of the soluble epidermal growth factor receptor (sEGFR/sErbB1) level in the periph-eral blood in development, invasiveness, apoplexy of each type of pituitary tumor. Methods The sEGFR level was d... To investigate effect of the soluble epidermal growth factor receptor (sEGFR/sErbB1) level in the periph-eral blood in development, invasiveness, apoplexy of each type of pituitary tumor. Methods The sEGFR level was determined in peripheral serum from 190 patients with pituitary diseases by enzyme linked immunosobent assay. The sEGFR levels were measured in 10 pituitary Rathke’s pouch, 18 pituitary hyperplasia, 161 pituitary adenomas including 30 microadenomas, 83 large adenomas, 48 giant adenomas, 1 pituitary carcinoma, and 28 hea-lthy controls. Results In the patients with pituitary hyperplasia, microadenoma, large adenoma, giant adenoma, and pituitary carci-noma, the sEGFR level was 188.92 ± 32.62, 209.83 ± 19.01, 333.20 ± 69.33, 405.85 ± 37.38, and 617.45 fmol/mL indepen-dently. They were all significantly higher than patients with pituitary Rathke’s pouch (156.78 ± 18.24 fmol/mL, P < 0.001) and healthy control group (159.11 ± 40.50 fmol/mL, P < 0.05). The sEGFR level in pituitary carcinoma was higher than pi-tuitary adenoma. In patients with pituitary adenoma, the sEGFR level was positive correlated to the size of pituitary adeno-mas (r = 0.998), the significant difference was observed for the sEGFR level in each group of the patients with pituitary adenomas (P < 0.001). Furthermore, in patients with pituitary ACTH-secreting microadenomas, the serum sEGFR levels in invasiveness (295.00 ± 77.80 fmol/mL) was higher than that in non-invasiveness (210.60 ± 16.4 fmol/mL, P < 0.05). In pati-ents with pituitary ACTH-secreting, PRL-secreting, GH-secreting, and non-functioning large adenomas, the serum sEGFR levels in invasiveness (407.86 ± 28.50, 399.25 ± 30.10, 386.00 ± 13.08, and 369.25 ± 36.70 fmol/mL) was higher than that in non-invasiveness (335.25 ± 63.49, 300.64 ± 47.57, 297.00 ± 61.93, and 269.30 ± 25.68 fmol/mL) respectively (P < 0.05). In patients with invasive pituitary PRL-secreting, GH-secreting, and non-functioning giant adenomas, the serum sEGFR levels not significantly different in between invasiveness (417.50 ± 35.94, 409.50 ± 69.14, and 417.50 ± 44.13 fmol/mL) and non-invasiveness (386.00 ± 49.64, 417.50 ± 44.03, and 409.51 ± 35.17 fmol/mL) (P > 0.05). In patients with pituitary large adeno-mas, the sEGFR levels in pituitary apoplexy (377.48 ± 39.18 fmol/mL) was higher than that in non-pituitary apoplexy (343.18 ± 68.17 fmol/mL, P > 0.05). Conclusions The increased level of peripheral serum sEGFR is concomitant with development, proliferous size of the adenomas in patients with pituitary adenomas. In addition, the elevated levels of serum sEGFR occur in pituitary apoplexy as clinical active tumors, and the non-invasive ACTH secreting adenomas. The sEGFR levels could be differen-tiated helpfully between pituitary adenomas and non-pituitary adenomas. These data suggest that serum sEGFR could be as a referable marker of the size and activation of proliferation in pituitary adenoma. 展开更多
关键词 pituitary adenoma pituitary carcinoma soluble epidermal growth factor receptor
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Differences in functional traits and reproductive allocations between native and invasive plants 被引量:6
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作者 WANG Cong-yan ZHOU Jia-wei +2 位作者 LIU Jun XIAO Hong-guang WANG Lei 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第3期516-525,共10页
Because co-occurring native and invasive plants are subjected to similar environmental selection pressures,the differences in functional traits and reproductive allocation strategies between native and invasive plants... Because co-occurring native and invasive plants are subjected to similar environmental selection pressures,the differences in functional traits and reproductive allocation strategies between native and invasive plants may be closely related to the success of the latter.Accordingly,this study examines differences in functional traits and reproductive allocation strategies between native and invasive plants in Eastern China.Plant height,branch number,reproductive branch number,the belowground-to-aboveground biomass ratio,and the reproductive allocation coefficient of invasive plants were all notably higher than those of native species.Additionally,the specific leaf area(SLA)values of invasive plants were remarkably lower than those of native species.Plasticity indexes of SLA,maximum branch angle,and branch number of invasive plants were each notably lower than those of native species.The reproductive allocation coefficient was positively correlated with reproductive branch number and the belowground-to-aboveground biomass ratio but exhibited negative correlations with SLA and aboveground biomass.Plant height,branch number,reproductive branch number,the belowground-to-aboveground biomass ratio,and the reproductive allocation coefficient of invasive plants may strongly influence the success of their invasions. 展开更多
关键词 functional trait specific leaf area reproductive allocation strategy phenotypic plasticity invasive plant
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A new algorithm for designing developable Bézier surfaces 被引量:3
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作者 ZHANG Xing-wang WANG Guo-jin 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第12期2050-2056,共7页
A new algorithm is presented that generates developable Bézier surfaces through a Bézier curve called a directrix. The algorithm is based on differential geometry theory on necessary and sufficient condition... A new algorithm is presented that generates developable Bézier surfaces through a Bézier curve called a directrix. The algorithm is based on differential geometry theory on necessary and sufficient conditions for a surface which is developable, and on degree evaluation formula for parameter curves and linear independence for Bernstein basis. No nonlinear characteristic equations have to be solved. Moreover the vertex for a cone and the edge of regression for a tangent surface can be obtained easily. Aumann’s algorithm for developable surfaces is a special case of this paper. 展开更多
关键词 Bézier surfaces Developable surfaces Bemstein basis Linear independence Characteristic equations
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Influence of microwave treatment under a hydrogen or methane atmosphere on the flotability of the macerals in Shenfu coals 被引量:15
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作者 Zhao Wei Yang Fusheng Li Yuangang Qu Jianlin Zhou Anning 《Mining Science and Technology》 EI CAS 2011年第6期761-766,共6页
The modification of Shenfu coals by a microwave treatment carried out under a hydrogen or a methane atmosphere, and the subsequent maceral separation by flotation, are described in this paper. The surface contact angl... The modification of Shenfu coals by a microwave treatment carried out under a hydrogen or a methane atmosphere, and the subsequent maceral separation by flotation, are described in this paper. The surface contact angle and the Zeta potential of the coal macerals were measured both with and without the treat- ment. The results show that the surface wettability of SFF (Shenfu Fusain) and SFV (Shenfu Vitrain) can be changed by the microwave treatment. An increase in the difference in surface wettability of SFF and SFV causes in a subsequent increase in the enrichment of inertinite and vitrinite. The results of the Zeta potential measurements show that the surface potentials of SFF and SFV are also changed by the treatment. 展开更多
关键词 Microwave Modification Maceral Flotation
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Viscosity of Sea Surface Microlayer in Jiaozhou Bay and Adjacent Sea Area 被引量:2
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作者 张正斌 张安慧 +3 位作者 刘莲生 刘春颖 任春艳 邢磊 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2003年第4期351-357,共7页
This study on the temporal and spatial variability of the viscosity and some chemical parameters in the sea surface microlayer (SML), the relationship between the viscosity and chemical parameters, and the influence o... This study on the temporal and spatial variability of the viscosity and some chemical parameters in the sea surface microlayer (SML), the relationship between the viscosity and chemical parameters, and the influence of the viscosity on the mass transfer coefficient ( K ) in the flux of materials through the air sea interface revealed that: The values of viscosity and some chemical parameters in the SML are higher than those in the sub surface layer (SSL), and at daytime are higher than those at night. The viscosity has positive corelation with chemical oxygen demand (COD), dissolved organic carbon (DOC) and salinity. The "SML effect" on K need not be considered because the SML effect on materials concentration is so small. 展开更多
关键词 VISCOSITY sea surface microlayer Jiaozhou Bay
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Comparative studies on phenotypic plasticity of two herbs,Changium smyrnioides and Anthriscus sylvestris 被引量:2
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作者 常杰 关保华 +1 位作者 葛滢 陈玉成 《Journal of Zhejiang University Science》 EI CSCD 2004年第6期656-662,共7页
The endangered medicinal herb, Changium smyrnioides can only be found in deciduous forest gaps within the middle to northern subtropical broad-leaved evergreen forest zone of China. The considerable plasticity of its ... The endangered medicinal herb, Changium smyrnioides can only be found in deciduous forest gaps within the middle to northern subtropical broad-leaved evergreen forest zone of China. The considerable plasticity of its shoot and root structure helps it to capture light more effectively in winter and early spring, and to adapt to the soil moisture conditions in its narrow habitat. Another medicinal plant, Anthriscus sylvestris, is of similar economic importance but commonly distributed widely. In contrast to C. smyrnioides, it has low structural plasticity. It is also specialized to adapt to the moist and sunny environment, where habitat, such as the banks of creeks and rivers, is abundant. 展开更多
关键词 Changium smyrnioides Anthriscus sylvestris Endangered species PLASTICITY Subtropical zone Winter species
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The Applicability of the Density Rule of Pathwardhan and Kumer and the Rule Based on Linear Isopiestic Relation 被引量:1
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作者 胡玉峰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第3期319-321,共3页
The applicability of the density rule of Pathwardhan and Kumer and the rule based on the linear isopiestic relation is studied by comparison with experimental density data in the literature. Predicted and measured val... The applicability of the density rule of Pathwardhan and Kumer and the rule based on the linear isopiestic relation is studied by comparison with experimental density data in the literature. Predicted and measured values for 18 electrolyte mixtures are compared. The two rules are good for mixtures with and without common ions, including those containing associating ions. The deviations of the rule based on the linear isopiestic relation are slightly higher for the mixtures involving very strong ion complexes, but the predictions are still quite satisfactory.The density rule of Pathwardhan and Kumer is more accurate for these mixtures. However, it is not applicable for mixtures containing non-electrolytes. The rule based on the linear isopiestic relation is extended to mixtures involving non-electrolytes. The predictions for the mixtures containing both electrolytes and non-electrolytes and the non-electrolyte mixtures are accurate. All these results indicate that this rule is a widely applicable approach. 展开更多
关键词 binary density rules DENSITY apparent molar volume multicomponent system binary sub-system
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Dependence of Softness on Fabric Surface Quality and Compressibility
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作者 胡吉永 丁辛 王如彬 《Journal of Donghua University(English Edition)》 EI CAS 2006年第5期59-63,共5页
The term "softness" is loosely used to describe the physical as well as sensory attributes of fabric and other textiles, and several psychophysicai evaluation methods as well as its predicting equations exist. Howev... The term "softness" is loosely used to describe the physical as well as sensory attributes of fabric and other textiles, and several psychophysicai evaluation methods as well as its predicting equations exist. However, the information for physiological mechanism of fabric softness is lack. To explain the blomechauical and the potential neurophysiologicai phecnomenon for exploring fabric softness, accompanying to the procedures in manual exploration for softness and the anatomical multllayor structures of human finer, a contact finite dement (FE) model between finger and fabric is made to conduct an active contact analysis. In present FE model, the effect of surface friction index, compression modulus, Poisson's ratio of fabric on softness dlscrimination is Investigated. The interests are in the contributlons of these fabric property variables to contact area, Interracial friction shear stress and contact pressure distributions, which arc significant cognitive variables or stimulus parameters in peripheral neural levels. The mechanistic data for fabric specimens indicates that the basis for the perception of softness of flexible and bulk fabric is likely on the spatial variation of pressure on the skin (or, equivalently the skin displacement and its derivatives) resulting from surface friction phenomenon and compression property of fabric. In present model, however, the effect of Poisson's ratio on the total force exerted by fingertip is not significant statistically. Therefore, compression modulus of fabric is, not the only underlying physical variable accounting for peripheral neural response, and also the surface friction phenomenon plays an important role in feeltouch softness of fabric, i.e. the compressibility and surface properties of fabric arc the necessary physical variables involved for the haptic rendering of its softness. 展开更多
关键词 FABRIC SOFTNESS FE model FRICTION compressibility.
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Phenotypic plasticity of floral traits and pollination adaption in an alpine plant Pedicularis siphonantha D. Don when transplanted from higher to lower elevation in Eastern Himalaya 被引量:2
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作者 DAI Wen-Kui AMBOKA Grace Mercy +2 位作者 KADIORI Edwin Luguba WANG Qing-Feng YANG Chun-Feng 《Journal of Mountain Science》 SCIE CSCD 2017年第10期1995-2002,共8页
Phenotypic plasticity and/or pollinatormediated selection may be responsible for the changes in floral traits of plants when they are forced to live in new conditions. Although the two events could be independent, we ... Phenotypic plasticity and/or pollinatormediated selection may be responsible for the changes in floral traits of plants when they are forced to live in new conditions. Although the two events could be independent, we hypothesized that phenotypic plasticity in floral traits might help to coordinate plant-pollinator interactions and enhance plant reproductive success in changing habitats. To test this hypothesis, we investigated floral traits and pollination on three natural populations of a lousewort(Pedicularis siphonantha) ranging at different elevations, as well as two downward transplanted populations in Shangeri-La County and Deqin County, northwest Yunnan, China. The results indicated that floral traits, i.e. phenology, longevity,display size, corolla tube length and pollen production differed significantly among populations. Moreover,or the two transplanted populations, floral traits diverged from their original populations, but converged to their host populations. Although the phenotypic plasticity in floral traits might be a rapid response to abiotic factor such as warmer environment, the changes in floral traits were found to be well adapted to pollination environment of the host population. Compared with plants of their original habitats in higher elevation, the transplanted individuals advanced flowering time, shortened flower longevity, reduced floral display size and pollen production, received higher visiting frequency and yielded more seeds. These findings suggested that phenotypic plasticity of floral traits might help plants adjust their resource allocation strategy between preand post-pollination stages in response to harsh or temperate conditions, which might correspondingly meet a pollinator-poor or hyphen rich environment.This would be beneficial for the widely-distributed species to adapt to various environmental changes. 展开更多
关键词 Alpine plant Bumble bee Pedicularis siphonantha Phenotypic plasticity in floral traits
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Indecomposable Representations of the Square—Root Lie Algebras of Vector Type and Their Boson Realizations 被引量:1
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作者 RUANDong YUANJing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第5期513-518,共6页
The explicit expressions for indecomposable representations of nine square-root Lie algebras of vector type, , are obtained on the space of universal enveloping algebra of two-state Heisenberg–Weyl algebra, the invar... The explicit expressions for indecomposable representations of nine square-root Lie algebras of vector type, , are obtained on the space of universal enveloping algebra of two-state Heisenberg–Weyl algebra, the invariant subspaces and the quotient spaces. From Fock representations corresponding to these indecomposable representations, the inhomogeneous boson realizations of are given. The expectation values of in the angular momentum coherent states are calculated as well as the corresponding classical limits. 展开更多
关键词 nonlinear Lie algebra indecomposable representation boson realization angular momentum coherent state
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