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“多功能”理念在儿童家具设计中的应用分析 被引量:1
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作者 邹采花 康丽娟 《工业设计》 2019年第1期60-61,共2页
本文通过调研市场现状,发现儿童家具已远远无法满足儿童以及家长的需求。阐述了新的"多功能"设计理念在儿童家具设计中的构建模式、方法等。目的是为了突破功能及娱乐一体化产品的局限。
关键词 儿童家具 “多功能” 情感需求
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N-doped ordered mesoporous carbon as a multifunctional support of ultrafine Pt nanoparticles for hydrogenation of nitroarenes 被引量:8
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作者 梁继芬 张晓明 +1 位作者 景铃胭 杨恒权 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第7期1252-1260,共9页
Due to the advantages of high surface areas, large pore volumes and pore sizes, abundant nitrogen content that favored the metal-support interactions, N-doped ordered mesoporous carbons are regarded as a kind ... Due to the advantages of high surface areas, large pore volumes and pore sizes, abundant nitrogen content that favored the metal-support interactions, N-doped ordered mesoporous carbons are regarded as a kind of fascinating and potential support for the synthesis of effective supported cat-alysts. Here, a N-doped ordered mesoporous carbon with a high N content (9.58 wt%), high surface area (417 m^2/g), and three-dimensional cubic structure was synthesized successfully and used as an effective support for immobilizing Pt nanoparticles (NPs). The positive effects of nitrogen on the metal particle size enabled ultrasmall Pt NPs (about 1.0 ± 0.5 nm) to be obtained. Moreover, most of the Pt NPs are homogeneously dispersed in the mesoporous channels. However, using the ordered mesoporous carbon without nitrogen as support, the particles were larger (4.4 ± 1.7 nm) and many Pt NPs were distributed on the external surface, demonstrating the important role of the nitrogen species. The obtained N-doped ordered mesoporous material supported catalyst showed excellent catalytic activity (conversion 100%) and selectivity (〉99%) in the hydrogenation of halogenated nitrobenzenes under mild conditions. These values are much higher than those achieved using a commercial Pt/C catalyst (conversion 89% and selectivity 90%). This outstanding catalytic perfor-mance can be attributed to the synergetic effects of the mesoporous structure, N-functionalized support, and stabilized ultrasmall Pt NPs. Moreover, such supported catalyst also showed excellent catalytic performance in the hydrogenation of other halogenated nitrobenzenes and nitroarenes. In addition, the stability of the multifunctional catalyst was excellent and it could be reused more than 10 times without significant losses of activity and selectivity. Our results conclusively show that a N-doped carbon support enable the formation of ultrafine metal NPs and improve the reaction ac-tivity and selectivity. 展开更多
关键词 N-doped mesoporous carbon Multifunctional support Ultrafine platinum nanoparticle Hydrogenation reaction Halogenated nitrobenzene
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The Influence of Plant Diversity and Functional Composition on Ecosystem Stability of Four Stipa Communities in the Inner Mongolia Plateau 被引量:65
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作者 白永飞 李凌浩 +1 位作者 黄建辉 陈佐忠 《Acta Botanica Sinica》 CSCD 2001年第3期280-287,共8页
The main purpose of this study was to examine the effects of plant species diversity and functional composition (the identity of the plant functional groups) on ecosystem stability of Stipa, communities in the Inner M... The main purpose of this study was to examine the effects of plant species diversity and functional composition (the identity of the plant functional groups) on ecosystem stability of Stipa, communities in the Inner Mongolia Plateau. The research work was based on a 12-year study (from 1984 to 1995) of species abundance, diversity, and primary productivity of four Stipa communities, i.e. S. baicalensis Roshev., S. grandis P. Smirn., S, krylovii Roshev., and S. klemenzii Roshev. respectively. The Shnnon-Wiener index was used as a measurement of plant diversity, while functional composition was used to differentiate the functional groups that were included in the communities. The plant species of four Stipa communities were classified into functional groups based on the differences in life forms and ecological groups, which influence their performance in resource requirements, seasonality of growth, tolerance to water stress, and life history. Plant species were classified into five functional groups based on their differences in life form, shrubs and half shrubs, perennial bunch grasses, perennial rhizome grasses, forbs, annuals and biennials. Based on their differences in water requirement these species were classified into four functional groups: xerads, intermediate xerads, intermediate mesophytes, and mesophytes. The results showed: 1) Plant species diversity stabilized ecosystem processes. Shannon-Wiener index were 2.401 4, 2.172 0, 1.624 8, 0.354 3 from S. baicalensis community to S. grandis, S. krylovii and S. klemenzii community, respectively. The dynamics of the aboveground net primary productivity (ANPP) for a 12-year's period showed a reverse pattern, the coefficients of variation of the four communities were 21.94%, 20.63%, 29.21% and 39.72% respectively. 2) The Life form functional group component of diversity was a greater determinant of the ecosystem processes than the species component of diversity. The effects of perennial bunch grasses, perennial rhizome grasses and forbs on community stability were highly significant. 3) The ecological group component of diversity was also a great determinant of the ecosystem processes. The effects of xerads, intermediate xerads, and mesophytes on community stability were also very strong. 展开更多
关键词 Inner Mongolia Plateau Stipa communities the aboveground net primary productivity species diversity functional composition
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Patterns of species diversity and functional diversity of breeding birds in Hangzhou across an urbanization gradient 被引量:3
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作者 李鹏 丁平 +2 位作者 Kenneth J.FEELEY 张竞成 蒋萍萍 《Chinese Birds》 2010年第1期1-8,共8页
Given the rapid rise in human population and increasing urbanization,it is important to understand their potential impacts on biodiversity.From March 2007 to August 2007,we conducted bird surveys in 90 strip transects... Given the rapid rise in human population and increasing urbanization,it is important to understand their potential impacts on biodiversity.From March 2007 to August 2007,we conducted bird surveys in 90 strip transects,each 3 km long and 100 m wide,along a gradient of urbanization in Hangzhou,China.This gradient spanned a range of urbanization levels including urban areas,rural-urban continuum areas,farming areas,mixed forest/farming areas and forested areas.We recorded 96 breeding bird species and classified them into nine functional groups based on nesting requirements.The nine functional groups consisted of canopy nesters,shrub nesters,canopy/shrub nesters,natural cavity nesters,building nesters,natural cavity/building nesters,ground nesters,water surface nesters and parasitic nesters.Species and functional diversities were estimated based on the Shannon-Wiener index.Environmental data of each transect as human disturbance,vegetation cover and building index were also measured,and a synthetic urbanization index of each transect was introduced based on these data.We used regression analyses to model the relationship of species abundance,species diversity,functional abundance and functional diversity with this synthetic index.The results show that urbanization significantly reduces species richness,species diversity,functional richness and functional diversity,but the specific patterns differed.The relationship between species abundance/species diversity and urbanization is linear.In contrast,the relationship between functional diversity and urbanization was quadratic.In other words,with increased urbanization,functional diversity declined only slightly at first but then dropped at an accelerating rate.This implies that,although moderate urbanization reduces species diversity of breeding birds,it affects functional diversity of breeding birds only slightly in Hangzhou.The regression analysis of species diversity and functional diversity suggests a quadratic relationship between species diversity and functional diversity,i.e.,a linear relationship between species diversity and functional diversity can only exist at low diversity levels across urbanization gradients and increasing species abundance does not lead to an increase in functional diversity at the highest diversity levels. 展开更多
关键词 URBANIZATION breeding bird community species diversity functional diversity Hangzhou
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Metabolic Characteristics and Functional Diversity of Carbon Source in Microflora of Ponds with Recirculating Aquaculture System 被引量:2
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作者 李谷 宋景华 +3 位作者 李晓莉 张世羊 陶玲 张春雪 《Agricultural Science & Technology》 CAS 2014年第2期278-282,299,共6页
With Biolog Eco microplate, metabolic characteristics and functional diver-sity of carbon source in microflora of ponds were researched based on recitculating ponds and control ponds in order to explore effects of eco... With Biolog Eco microplate, metabolic characteristics and functional diver-sity of carbon source in microflora of ponds were researched based on recitculating ponds and control ponds in order to explore effects of eco-adjustments on microflo-ra in ponds. The results indicate that total number of bacterium, microbial metabolism activity, and diversity index in P7, P8, P1 and P2 kept higher, fol owed by P3, P4, P5 and P6. The utilization rate of microbes on sugars achieved the highest (31.0%-48.7%), fol owed by carboxylic acid (13.4%-18.0%), amino acid (10.1%-20.5%), polymers (9.4%-17.0%), biopolymer (5.7%-9.7%) and phenol (4.95%-7.50%). Principal component analysis divided microflora in different ponds, suggesting that microbial community has varied carbon source characteristics and nitrogen-containing compound and biopolymer metabolisms are most affected. 展开更多
关键词 Aquaculture pond MICROBE -Metabolic characteristics of carbon source Functional diversity
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Screening of Preprocessing Method of Biolog for Soil Microbial Community Functional Diversity 被引量:2
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作者 党雯 郜春花 +4 位作者 张强 李建华 卢朝东 靳东升 卢晋晶 《Agricultural Science & Technology》 CAS 2015年第10期2247-2251,2255,共6页
As one of the main methods of microbial community functional diversity measurement, biolog method was favored by many researchers for its simple oper- ation, high sensitivity, strong resolution and rich data. But the ... As one of the main methods of microbial community functional diversity measurement, biolog method was favored by many researchers for its simple oper- ation, high sensitivity, strong resolution and rich data. But the preprocessing meth- ods reported in the literatures were not the same. In order to screen the best pre- processing method, this paper took three typical treatments to explore the effect of different preprocessing methods on soil microbial community functional diversity. The results showed that, method B's overall trend of AWCD values was better than A and C's. Method B's microbial utilization of six carbon sources was higher, and the result was relatively stable. The Simpson index, Shannon richness index and Car- bon source utilization richness index of the two treatments were B〉C〉A, while the Mclntosh index and Shannon evenness were not very stable, but the difference of variance analysis was not significant, and the method B was always with a smallest variance. Method B's principal component analysis was better than A and C's. In a word, the method using 250 r/min shaking for 30 minutes and cultivating at 28 ℃ was the best one, because it was simple, convenient, and with good repeatability. 展开更多
关键词 Biolog method Preprocessing method Soil microbial community Func- tional diversity AWCD values
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Discussion on Structure Evolution and Function Expansion of Agriculture in China 被引量:1
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作者 刘新 《Agricultural Science & Technology》 CAS 2009年第2期145-148,153,共5页
According to the characteristics of agricultural development during different periods, agricultural development was basically divided into traditional period, planning system period and household contracting pedod to ... According to the characteristics of agricultural development during different periods, agricultural development was basically divided into traditional period, planning system period and household contracting pedod to discuss the related laws of agricultural development in China. The agricultural function expansion during different periods was analyzed in terms of agricultural structure evolution, while structural optimization and function expansion of modem agriculture in China were also studied. The results indicated that during the traditional period, agricultural structure emphasized feeding people and grain production while agricultural function reflected the economic function beyond surviving standard. During the planning system period, a unitary structural mode of agriculture was formed in China, which showed that agriculture was dominated by planting industry and planting industry was dominated by grain, while agriculture executed the mixed economic function beyond surviving and liv- ing standard. During the household contracting period, the industrial structure of agriculture in China gradually became diversification and optimi- zation, but as the economic function of industrial standard, agricultural development was still greatly inhibited. The structural evolution of modem agriculture in China must step forward towards collectivization and scale merit, while ecological function and social function of agriculture increas- ingly become important and the function of agricultural production becomes mere and more diverse. 展开更多
关键词 Agricultural structure Agricultural function Multi-functional agriculture
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Effects of Compound Phellinus igniarius(L.ex Fr.)Quel. Oral Liquid's Polysaccharide on the Immunologic Function of Mice 被引量:8
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作者 傅海庆 林希 +2 位作者 傅华英 蔡玮 陈团伟 《Agricultural Science & Technology》 CAS 2015年第6期1290-1294,共5页
In this paper, the effects of compound P. igniarius oral liquid’s crude polysaccharide on the immunologic function of mice were studied from four aspects, namely, carbon clearance test of mice, macrophage phagocytosi... In this paper, the effects of compound P. igniarius oral liquid’s crude polysaccharide on the immunologic function of mice were studied from four aspects, namely, carbon clearance test of mice, macrophage phagocytosis of chicken red blood cel s in the enterocoelia of mice (semi-in vivo method), the ratio of organ to body weight, natural kil er (NK) cel activity in mice (the determination of lactate de-hydrogenase assay). The results showed that high-dosage group(40 mL/kg) of com-pound P. igniarius oral liquid can obviously enhance the ability of carbon clearance of mice; middle-(20 mL/kg) and high-dosage groups can significantly enhance the phagocytic rate and phagocytic index of chicken erythrocyte of mouse macrophage;low-(10 mL/kg), middle- and high-dosage groups can significantly enhance NK cel activity of mice. These showed that compound P. igniarius oral liquid can enhance mononuclear-macrophage and NK cel activity. In conclusion, compound P. igniarius oral liquid’s polysaccharide can enhance immunologic function and significantly im-prove the specific and nonspecific immunologic function. 展开更多
关键词 Compound Phel inus igniarius oral liq-uid Crude polysaccharide MICE Immunologic function
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Status of urban vegetation in Guangzhou City 被引量:12
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作者 管东生 陈玉娟 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第3期249-252,共4页
According to a survey for the urban vegetation of Guangzhou, urban vegetation has a significantly difference from natural vegetation because of intense human impacts. The research was conducted in a synthetic survey f... According to a survey for the urban vegetation of Guangzhou, urban vegetation has a significantly difference from natural vegetation because of intense human impacts. The research was conducted in a synthetic survey for soil, species di-versity, roadside trees and ecological function of urban vegetation in Guangzhou City. The results showed that: (1) soil densi-ties of urban roadside and park forests were higher than mean density of natural forest soil. The pH values of soil in urban roadside were higher too, and the content of organic matter and the concentration of nitrogen were lower. (2) Species diversity of urban vegetation was lower. The most number of species was only 16 species in tree layers of urban forest. (3) Tree growth was limited by narrow space in high-density urban area, where the trees with defects and disorders were common. (4) Com-paring with mature natural forests, the productivity of urban vegetation was lower. The effect of urban vegetation on balance of carbon and oxygen were influenced by the low primary production of urban vegetation. Therefore, the growth condition for urban vegetation should be improved. Biodiversity, primary production and ecological function should be increased for urban vegetation in order to improve urban eco-environment. 展开更多
关键词 Urban vegetation STATUS Human impact
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Clinical Features of Renal Insufficiency due to Multiple Myeloma and Related Risk Factors 被引量:1
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作者 刘雪梅 徐金兰 +1 位作者 官旭华 刘丽秋 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第1期47-49,68,共4页
Objective: To study clinical features of the patients with multiple myeloma(MM) accompanied by renal insufficiency and investigate the related risk factors of renalimpairment. Methods: A control study of clinical char... Objective: To study clinical features of the patients with multiple myeloma(MM) accompanied by renal insufficiency and investigate the related risk factors of renalimpairment. Methods: A control study of clinical characteristics was performed between 91 patientswith renal insufficiency due to MM and 165 patients with normal renal function in MM during the sameperiod. The data were statistically analyzed by chi-square test and logistic regression analysis.Results: Renal insufficiency was the initial presentation in 48 (52.7%) of the 91 patients, and 30(62.5%) of the 48 patients were misdiagnosed. The prognosis of group with renal insufficiency wassignificantly poorer than that of group with normal renal function: mortality in 3 months, 3months-1 year was 26/91 vs 14/165 (P 【 0.0001), 14/91 vs 12/165 (P 【 0.05) respectively, andpatients survived 】 1 year was 18/91 vs 95/165 (P 【 0.0001). The incidence of hypercalcemia,hyperuricemic, severe anemia, high serum M-protein concentration and lytic bone lesions weresignificantly higher in renal insufficiency group than those in control group (P 【 0.05). Logisticregression analysis identified 5 risk factors of renal impairment, including, severe anemia(Exp(β)=13.819, P 【 0.0001), use of nephrotoxic drugs (Exp(β)=6.217, P = 0.001), high serumM-protein concentration (Exp(β) = 5.026, P = 0.001), male (Exp(β)=3.745, P=0.006), andhypercalcemia (Exp(β)=3A72, P=0.006), but age, serum density of uric acid, type of serum M-protein,and Bence Jones proteinuria were not significantly associated with renal insufficiency. Conclusion:Renal insufficiency was a common early complication of MM, which often resulted in misdiagnosis.The status of these patients tended to be very bad, with many other complications, when MM wasdiagnosed, so their prognosis was poor. The occurrence of renal insufficiency in patients with MMand hypercalcemia, severe anemia, high serum M-protein concentration, especially use of nephrotoxicdrugs should be alert. 展开更多
关键词 multiple myeloma renal insufficiency clinical feature risk factor
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Research on Stoichiometry of Early-spring Herbs Functional Group in the Subtropical Artificial Wetland
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作者 牛晓音 常杰 +1 位作者 葛滢 郑家文 《Agricultural Science & Technology》 CAS 2011年第8期1182-1185,1190,共5页
[Objective]The aim was to carry out stoichiometry on the early-spring herbs functional group in subtropical artificial wetland.[Method]UV-Vis spectrophotometer was used for the determination of nitrate-nitrogen,ammoni... [Objective]The aim was to carry out stoichiometry on the early-spring herbs functional group in subtropical artificial wetland.[Method]UV-Vis spectrophotometer was used for the determination of nitrate-nitrogen,ammonium nitrogen and phosphorus concentrations.Potassium persulfate absorptiometry was used for the measurement of total N content,while the flame photometer was used to detect the potassium and sodium concentration in plants.All the nutrient determination of plant samples were repeated for four times.[Result]The four nutrient concentrations in almost all samples were in the normal range of natural plant nutrition concentrations;in early-spring herbs functional groups,different species showed diversity on the nutrient concentrations;plant height had no significant effect on the nutrient concentrations in plants;the nutrient concentrations of non-grass group plants were higher than that of grass group plants;the nutrient concentrations of the annual herb were higher than that of perennial herbs.[Conclusion]The study had provided basis for the understanding of the effects of changes in nutritional conditions on species diversity,community structure and succession of the system. 展开更多
关键词 Early-spring herbs Functional group BIODIVERSITY Element STOICHIOMETRY
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Blind multiple watermarking algorithm for audio 被引量:2
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作者 陈宁 朱杰 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期206-210,共5页
To make digital watermarking accomplish several goals, a new method for simultaneously embedding multiple watermarks into the same audio signal is proposed. First, the original audio signal is segmented into frames of... To make digital watermarking accomplish several goals, a new method for simultaneously embedding multiple watermarks into the same audio signal is proposed. First, the original audio signal is segmented into frames of appointed lengths and all the element watermarks are encoded to achieve a mixed watermark. Then, the binary bits in the mixed watermark are embedded into the audio frames with the echo hiding technique. The watermark extraction can be performed without an original audio signal. Furthermore, in order to enhance the extraction accuracy and the robustness of the proposed algorithm against common signal manipulations, the autocorrelafion of the power cepstrum is utilized to estimate the echo delays in the watermarked audio frames to extract the mixed watermark and the corresponding decoding method is applied to achieve the element watermarks. Computer simulation results indicate that the proposed scheme has great robustness against common signal manipulations of Mp3 compressing, re-sampling, re-quantizing, low-pass filtering and white noise addition. 展开更多
关键词 multiple watermarking echo hiding power cepstrum blind detection
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Protective Effect of phytolacca Acinosa Polysaccharides Ⅰ(PAP-Ⅰ)on Hematopoiesis in Cyclophosphamide-treated and 60 ̄Co-irradiated Mice
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作者 王洪斌 郑钦岳 +5 位作者 孙盛川 刘宝云 沈有安 唐惠兰 鞠佃文 方军 《Journal of Chinese Pharmaceutical Sciences》 CAS 1995年第2期89-98,共10页
The protective effect of a kind of purified polysaccharides extracted from Radix of Phytolacca acinosa Roxb,with a molecular weight of 10 KDa,on hematopoiesis was investigated.Average survival time of mice treated wit... The protective effect of a kind of purified polysaccharides extracted from Radix of Phytolacca acinosa Roxb,with a molecular weight of 10 KDa,on hematopoiesis was investigated.Average survival time of mice treated with cyclophosphamide (CY) 300 mg/kg once alone was 13.3 ± 7.2d(n=7) however,average survival time of mice treated with CY 300 mg/kg in com-bination with PAP-1 10 mg/kg,3 times/wk was 36.7± 16.4d(n=7,P<0.01).PAP-1,ip had benefi-cial effect on the recovery of the CY induced decrease of peripheral leukocyte number,and the nu-cleated bone marrow cell(BMC)number and[3 ̄H]TdR uptaken by BMC induced by rmGM-CSF in S180 bearing mice treated with CY,In mice,after the first ip treatment with CY 100 mg/kg on d7,the peripheral leukocyte number decreased on d9 and recovered to normal level about d13 to d15. Such recovery was accelerated by administrating PAP-1,10mg/kg, 3 times/wk.A significant in-crease of the activity to form colony in spleen(colony-forming unit in spleen, CFU-S_8, CUF-S12) in mice irradiated with 550 rad 6O ̄Co γ-rays and an enhancement of proliferative response of BMC to rmGM-CSF treated with PAP-1,10mg/kg,3 times/wk, ip were observed.After PAP-1,10 mg/kg,ip once,a significant increase in the number of peripheral blood leukocytes and a rise in the serum of colony stimulating factor(CSF) were also confirmed.The types of CSF in serum were M-CSF and other hematopoietic growth factors,which were confirmed by using McAb of IL-3, GM-CSF and PcAb of M-CSF. These beneficial effects of PAP-1 on hematopoiesis may be related to its activityinducing CSFs and other hematopoietic growth factors and warrant further evaluation of its use-fulness. 展开更多
关键词 Phytolacca acinosa POLYSACCHARIDES CYCLOPHOSPHAMIDE Colony-forming unit in spleen(CFU- Colony stimulating factors Monocolonal antibody Polycolonal antibody
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Fabricating multifunctional polymeric nanofilm capable of resisting corrosion and activating copper surface by electrochemical and hydrolysis-condensation approach 被引量:1
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作者 王亚斌 黄玉东 亓玉台 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第11期2947-2959,共13页
A multifunctional polymeric nanofilm of triazinedithiolsilane monosodium salt, which can resist corrosion and activatecopper surface concurrently, was prepared by galvanostatic technique and the following hydrolysis-c... A multifunctional polymeric nanofilm of triazinedithiolsilane monosodium salt, which can resist corrosion and activatecopper surface concurrently, was prepared by galvanostatic technique and the following hydrolysis-condensation approach.Electrochemical tests were carried out to evaluate the resistant ability of nanofilm. The changes of functional groups atop thenanofilms were monitored with Fourier transform infrared spectroscopy (FT-IR) and contact angles (CA) simultaneously. Thechemical composition and the morphology of the polymeric nanofilm were investigated by X-ray photoelectron spectroscopy (XPS)and scanning electron microscope (SEM), respectively. The results reveal that the preferentially developed disulfide units protect thecopper during the whole preparation process, and the subsequently hydrolyzed nanofilms without/with heating shape into newinterface phases bearing the multifunctionality. This multifunctional interface (the polymeric nanofilm on copper surface) opens upthe possibilities for other OH-containing reagents to be anchored onto copper surface in demanding researches or industrialapplications. 展开更多
关键词 copper triazinedithiolsilane galvanostatic technique multifunctional polymeric nanofilm functionalized interface
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Construction of Double Cross-over Expression Vector for Chloroplast Multicistron in Brassica napus L. 被引量:1
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作者 武玉永 姚庆收 马立新 《Agricultural Science & Technology》 CAS 2013年第3期402-406,共5页
[Objective] This study aimed to construct Brassica napus chloroplast multi- cistron double cross-over expression vector, to lay the foundation for the genetic engi- neering research of Brassica napus chloroplast. [Met... [Objective] This study aimed to construct Brassica napus chloroplast multi- cistron double cross-over expression vector, to lay the foundation for the genetic engi- neering research of Brassica napus chloroplast. [Method] Two primers were designed based on the known Brassica napus chloroplast DNA sequences AF267640 and Z50868 in GenBank. By using PCR method, two Brassica napus L. chloroplast DNA fragments were obtained, which were named RbcL and ACCD. The two Brassica na- pus chloroplast DNA homologous fragments were then cloned into plasmid pMD18-T to obtain recombinant plasmid pHBM715. Tandem expression cassette harboring spectinomycin-resistant gene aadA, mannanase gene man and green fluorescent pro- tein gene gfp was cloned into the plasmid pHBM715, thereby constructing Brassica napus chloroplast multicistron double cross-over expression vector pHBM716, which was transformed into Escherichia coil for expression and identification. [Result] Plate qualitative analysis was conducted for the functional identification of expression cas- sette in the constructed Brassica napus chloroplast multicistron double cross-over ex- pression vector, results showed that the three genes of the same multicistron were all expressed in E. coil [Conclusion] This study successfully constructed Brassica napus chloroplast multicistron double cross-over expression vector, which laid the foundation for the genetic engineering of Brassica napus chloroplast. 展开更多
关键词 Brassica napus L. Chloroplast DNA Multicistron Double cross-over Expression vector Functional identification
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TGF-β1-promoted epithelial-to-mesenchymal transformation and cell adhesion contribute to TGF-β1-enhanced cell migration in SMMC-7721 cells 被引量:30
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作者 ZHENXU MINXIONGSHEN +2 位作者 DONGZHUMA LIYINGWANG XILIANGZHA 《Cell Research》 SCIE CAS CSCD 2003年第5期343-350,共8页
Transforming growth factor-b 1 (TGF-β1), a multi-function polypeptide, is a double-edged sword in cancer. For some tumor cells, TGF-β1 is a potent growth inhibitor and apoptosis inducer. More commonly, TGF-β1 loses... Transforming growth factor-b 1 (TGF-β1), a multi-function polypeptide, is a double-edged sword in cancer. For some tumor cells, TGF-β1 is a potent growth inhibitor and apoptosis inducer. More commonly, TGF-β1 loses its growth-inhibitory and apoptosis-inducing effects, but stimulates the metastatic capacity of tumor cells. It is currently little known about TGF-β1-promoted cell migration in hepatocellular carcinoma (HCC) cells, let alone its mechanism. In this study, we found that TGF-β1 lost its tumor-suppressive effects, but significantly stimulated cell migration in SMMC-7721 human HCC cells. By FACS and Western blot analysis, we observed that TGF-β1 enhanced the expression of α5β1 integrin obviously, and subsequently stimulated cell adhesion onto fibronectin (Fn). Furthermore, we observed that TGF-β1 could also promote SMMC-7721 cells adhesion onto laminin (Ln). Our data also provided evidences that TGF-β1 induced epithelial-to-mesenchymal transformation (EMT) in SMMC-7721 cells. First, SMMC-7721 cells clearly switched to the spindle shape morphology after TGF-β1 treatment. Furthermore, TGF-β1 induced the down-regulation of E-cadherin and the nuclear translocation of β-catenin. These results indicated that TGF-β1-promoted cell adhesion and TGF-β1-induced epithelial-to-mesenchymal transformation might be both responsible for TGF-β1-enhanced cell migration. 展开更多
关键词 TGF-Β1 cell migration epitheIial-to-mesenchymal transformation α5β1 integrin.
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The Herpes Simplex Virus Type 1 Multiple Function Protein ICP27 被引量:6
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作者 Lei ZHAO Wen-bo ZHU Qiong DING Gui-qing PENG Chun-fu ZHENG 《Virologica Sinica》 SCIE CAS CSCD 2008年第6期399-405,共7页
The herpes simplex virus type 1 (HSV-1) infected-cell protein 27 (ICP27) is an essential, highly conserved protein involved in various steps of HSV-1 gene regulation as well as in the shut-off of host gene express... The herpes simplex virus type 1 (HSV-1) infected-cell protein 27 (ICP27) is an essential, highly conserved protein involved in various steps of HSV-1 gene regulation as well as in the shut-off of host gene expression during infection. It functions primarily at the post-transcriptional level in inhibiting precursor mRNA splicing and in promoting nuclear export of viral transcripts. Recently, many novel functions performed by the HSV- 1 ICP27 protein were shown, including leptomycin B resistance, inhibition of the type I interferon signaling, regulation of the viral mRNA translation and determining the composition of HSV-1 virions 展开更多
关键词 Herpes simplex virus type 1 (HSV-1) Infected-cell protein 27 (ICP27) Nuclear export LeptomycinB (LMB) Interferon (IFN)
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Purification and Characterization of a Versatile Peroxidase from Edible Mushroom Pleurotus eryngii 被引量:8
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作者 陈敏 姚善泾 +1 位作者 张虹 梁新乐 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第5期824-829,共6页
A versatile peroxidase (VP-Peco60-7 ) was generated and purified from the liquid culture of Pleurotus eryngii. The purification procedure included ammonium sulfate precipitation, ion exchange chromatography, and gel c... A versatile peroxidase (VP-Peco60-7 ) was generated and purified from the liquid culture of Pleurotus eryngii. The purification procedure included ammonium sulfate precipitation, ion exchange chromatography, and gel chromatography. The molecular weight and isoelectric point (pI) of VP-Peco60-7 were determined to be approxi-mately 40 kDa and 4.1, respectively. By N-terminal sequence determination and peptide mapping analysis, VP-Peco60-7 was found to be similar to the versatile peroxidase isoenzyme VPL1, which was previously isolated from liquid cultures of the same species. However, the molecular weight and pI of VP-Peco60-7 were different from those of versatile peroxidases of liquid cultures, implying that the VP-Peco60-7 in this study is of a novel type. With 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) as a substrate, the maximal enzyme activity was obtained at 50 °C and pH 3.0. The catalysis of ABTS by VP-Peco60-7 was expressed by the Michaelis-Menten equa-tion. At 50 °C and pH 3.0, the maximum velocity (V max ) was 188.68 U·mg-1 and the michaelis constant (K m ) was 203.09 μmol·L-1 . 展开更多
关键词 Pleurotus eryngii versatile peroxidase PURIFICATION enzymatic properties
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Fog Detection over China's Adjacent Sea Area by using the MTSAT Geostationary Satellite Data 被引量:8
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作者 LI Jun 1,2,HAN Zhi-Gang 3,CHEN Hong-Bin 1,ZHAO Zeng-Liang 3,and WU Hong-Yi 4 1 Laboratory for Middle Atmosphere and Global Environment Observation (LAGEO),Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,China 2 Graduate University of Chinese Academy of Sciences,Beijing 100049,China 3 Beijing Institute of Applied Meteorology,Beijing 100029,China 4 Beijing Meteorological Bureau,Beijing 100089,China 《Atmospheric and Oceanic Science Letters》 2012年第2期128-133,共6页
A fog threshold method for the detection of sea fog from Multi-function Transport Satellite (MTSAT1R) infrared (IR) channel data is presented.This method uses principle component analysis (PCA),texture analysis,and th... A fog threshold method for the detection of sea fog from Multi-function Transport Satellite (MTSAT1R) infrared (IR) channel data is presented.This method uses principle component analysis (PCA),texture analysis,and threshold detection to extract sea fog information.A heavy sea fog episode that occurred over China's adjacent sea area during 7 8 April 2008 was detected,indicating that the fog threshold method can effectively detect sea fog areas nearly 24 hours a day.MTSAT-1R data from March 2006,June 2007,and April 2008 were processed using the fog threshold method,and sea fog coverage information was compared with the meteorological observation report data from ships.The hit rate,miss rate,and false alarm rate of sea fog detection were 66.1%,27.3%,and 33.9%,respectively.The results show that the fog threshold method can detect the formation,evolution,and dissipation of sea fog events over period of time and that the method has superior temporal and spatial resolution relative to conventional ship observations.In addition,through MTSAT-1R data processing and a statistical analysis of sea fog coverage information for the period from 2006 to 2009,the monthly mean sea fog day frequency,spatial distribution and seasonal variation characteristics of sea fog over China's adjacent sea area were obtained. 展开更多
关键词 sea fog MTSAT geostationary satellite spatial distribution seasonal variation
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A new multifunctional polymer:Synthesis and characterization of mPEG-b-PAA-grafted chitosan copolymer 被引量:4
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作者 刘承斌 王小见 +2 位作者 刘荣华 吴育林 罗胜联 《Journal of Central South University》 SCIE EI CAS 2010年第5期936-942,共7页
A new multifunctional mPEG-b-PAA-grafted chitosan copolymer possessing amino and carboxyl groups,mPEG-b-PAA-g-CHI(compound 6) ,was designed for a potential application in gene/drug delivery and synthesized by the meth... A new multifunctional mPEG-b-PAA-grafted chitosan copolymer possessing amino and carboxyl groups,mPEG-b-PAA-g-CHI(compound 6) ,was designed for a potential application in gene/drug delivery and synthesized by the methods of reversible addition-fragmentation chain transfer(RAFT) polymerization of acrylic acid(AA) and grafting reaction of a biodegradable chitosan(CHI) derivative.Completion of the reactions and characterization of the resulting compounds were demonstrated by 1 H NMR,FTIR and gel permeation chtomatography(GPC) studies.The results show that the molar ratio of amino groups to carboxyl groups in the copolymer(compound 6) is 0.41-0.59. 展开更多
关键词 CHITOSAN polyacrylic acid (PAA) polyethylene glycol (PEG) multifunction polymer synthesis characterization
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