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35篇 您的检索式:作者名="Hewen"
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1Relationships between vegetation and stomata,and between vegetation and pollen surface soil in Yunnan,Southwest China显示文摘Surface pollen and stomata of 61 samples collected in a study area ranging from tropical seasonal rainforest to oak forest(Quercus spinosa) in the Yulong Snow Mountain region in Yunnan,China,are used to distinguish vegetation communities.The results show that tropical seasonal rainforest(and mountain rainforest),south subtropical evergreen broad-leaved forest,and Quercus shrub are distinguished effectively from other vegetation types by analysis of surface pollen.The south subtropical evergreen broad-leaved forest,Pinus kesiya forest and evergreen broadleaf forest are distinguished effectively from other types of vegetation by pollen analysis.However,P.yunnanensis forest is not distinguished from other vegetation types,and P.armandii,P.densata forest and temperate deciduous conifer mixed forest are not distinguished.The over-representation of Pinus pollen is the main reason that these vegetation communities are not distinguished from each other.Conifer stomata analysis is an effective tool for identifying and distinguishing different types of coniferous forest,and this method performs well even with a small number of sampling points.SHEN HuaDong LI ChunHai WAN HeWen TONG GuoBang LIU JinSong DAN Johnson 2013Chinese Science Bulletin2013,58,15:12
2Efficiency Analysis of Industrial Water Treatment in China Based on Two-stage Undesirable Fixed-sum Output DEA Model显示文摘China is a country with the most water consumption, so it is lack of water resources.Industry has brought serious water pollution while driving economic development, which leads to the destruction of ecological environment. With the improvement of environmental awareness, many scholars have shifted their research direction to how to improve the ecological environment. Most studies consider the whole system as a 'black box', regardless of its internal structure. Therefore, a method to identify inefficiency is necessary and some suggestions for optimization are given. In this paper,a two-stage undesirable fixed-sum output data envelopment analysis(DEA) model is proposed. The industrial chemical oxygen demand(COD) emission during 2011–2015 are adjusted, and the efficiency values are calculated by heuristic search algorithm. The efficiency of 30 provinces and cities is divided into eastern, central and western regions. The model can identify the inefficient stage in industrial system, and find the source of low efficiency in the system. The analysis shows that the efficiency of eastern region is the highest, while the overall efficiency is inclined to the pollutant treatment stage.Finally, the paper puts forward some suggestions for the low efficiency areas, which can save water while ensuring economic benefits, and provide new direction for water pollution reduction and improve the ecological environment.Hewen MA Baoxia GENG Yingxiong FU Yi SUN Zhao SUN 2021Journal of Systems Science and Information2021,9,6:5
3Immune responses of a designed HIV-1 DNA vaccine on rhesus monkeys显示文摘An effective HIV-1 vaccine will be the ultimate solution for the prevention of HIV/AIDS, though HAART plays important roles in treating the disease. In this study, a large-scale recombinant DNA plasmid containing a designed HIV-1 multi-epitope- p24 chimeric gene was prepared and purified. Rhesus monkeys were then inoculated muscularly with the plasmid for four times in week 0, 4, 8 and 18. Whole blood was collected two weeks after the third and fourth inoculation, followed by serum and pe- ripheral blood mononuclear cell (PBMC) separation. The CTL activity and proliferation of PBMCs stimu- lated by macaque MHC-I-restricted HIV-1 CTL epi- tope peptide were analyzed by MTT and LDH release assay, respectively. Th1 cytokines in supernatant of cultured PBMC stimulated by HIV-1 CTL epitope peptide and anti-HIV-1 antibody in serum were as- sayed by ELISA. The results showed that increased CTL target-killing activity, higher secretion of Th1 cytokines (IFN-γ and IL-2) and promoted proliferative reaction of monkey PBMCs stimulated by HIV-1 CTL epitope peptide were detected in the immunization group inoculated by the recombinant DNA vaccine for three times, which were further enhanced by the fourth inoculation. At the same time, HIV-1 specific antibody in serum of immunized monkeys was higher than that in controls. We concluded that the designedHIV-1 DNA vaccine may induce HIV-1 specific cellular and humoral immunity on monkeys.ZHANG Lishu JIN Ningyi SONG Yingjin SUN Yansong WANG Hong ZHAN Dawei MA Hewen SHANG Yupu JIN Hongtao HONG Baoqing LI Chang 2006Chinese Science Bulletin2006,51,13:3
4Trace elements and rare earth elements in wet deposition of Lijiang,Mt.Yulong region,southeastern edge of the Tibetan Plateau显示文摘In order to investigate the compositions and wet deposition fluxes of trace elements and rare earth elements(REEs) in the precipitation of the southeastern edge of the Tibetan Plateau, 38 precipitation samples were collected from March to August in 2012 in an urban site of Lijiang city in the Mt. Yulong region. The concentrations of most trace elements and REEs were higher during the non-monsoon season than during the monsoon season,indicating that the lower concentrations of trace elements and REEs observed during monsoon had been influenced by the dilution effect of increased precipitation. The concentrations of trace elements in the precipitation of Lijiang city were slightly higher than those observed in remote sites of the Tibetan Plateau but much lower than those observed in the metropolises of China, indicating that the atmospheric environment of Lijiang city was less influenced by anthropogenic emissions, and, as a consequence, the air quality was still relatively good. However, the results of enrichment factor and principal component analysis revealed that some anthropogenic activities(e.g., the increasing traffic emissions from the rapid development of tourism) were most likely important contributors to trace elements, while the regional/local crustal sources rather than anthropogenic activities were the predominant contributors to the REEs in the wet deposition of Lijiang city. Our study was relevant not only for assessing the current status of the atmospheric environment in the Mt. Yulong region, but also for specific management actions to be implemented for the control of atmospheric inputs and the health of the environment for the future.Junming Guo Shichang Kang Jie Huang Mika Sillanpaa Hewen Niu Xuejun Sun Yuanqing He Shijing Wang Lekhendra Tripathee 2017Journal of Environmental Sciences2017,29,2:3
5Effects of Exogenous 5-Aminolevulinic Acid and 24-Epibrassinolide on Cd Accumulation in Rice from Cd-Contaminated Soil显示文摘High grain-Cd-accumulating rice variety Yongyou 9 was planted in Cd-contaminated farmland in Taizhou City, Zhejiang Province, China to study the effects of 5-aminolevulinic acid(ALA) and24-epibrassinolide(EBR) on Cd accumulation in brown rice. Results showed that the exogenous ALA and EBR had no significant effects on agronomic traits, soil pH and total Cd content in soil, but had some effects on the available Cd content in soil, and significantly influenced the Cd accumulation in the different parts of rice. Results also showed that 100 mg/L exogenous ALA significantly reduced the Cd accumulation in brown rice to blow the food safety standard(0.2 mg/kg), and also significantly reduced the Cd contents in the roots and culm of rice. However, 200 mg/L exogenous ALA treatment increased the Cd content in brown rice remarkably. In addition, 0.15 mg/L EBR treatment increased Cd accumulation in roots, culm, leaves and brown rice notably, whereas 0.30 mg/L exogenous EBR treatment reduced the Cd accumulation in brown rice properly, but it was not significant. Therefore,proper concentration of ALA can effectively reduce the Cd accumulation in brown rice, which can be used as an effective technical method for the safe production of rice in Cd polluted farmland.WANG Feijuan ZHANG Yiting GUO Qinxin TAN Haifeng HAN Jiahui LIN Haoran WEI Hewen XU Guangwei ZHU Cheng 2018Rice science2018,25,6:3
6Macroporous-mesoporous C-,S-,N-doped titania microspheres via the polyHIPE microspheres templates显示文摘Doping and increasing specific surface area by forming highly porous structures are two effective ways to enhance the photocatalytic performances of TiO_(2) particles.He re for the first time,we report a new facile method to prepare the macroporous-mesoporous C-,S-,N-doped TiO_(2)(C/S/N-TiO_(2))microspheres via polyHIPE microsphe res as templates.The chemical and crystalline structure s of these hierarchical porous TiO_(2) microspheres are analyzed with FTIR,XPS,EDS,and XRD.The macroporous-mesoporous structures are confirmed with SEM observation and BET analysis.UV-vis DRS spectra analysis shows that the band gaps of C doped TiO_(2),C/N doped TiO_(2),C/S doped TiO_(2) and C/S/N doped TiO_(2) are estimated to be 3.07,3.01,2.94 and 2.81 eV,respectively,which are significantly narrower than that of TiO_(2) nanoparticles(3.23 eV).Photoluminescence spectra demonstrate that the recombination of electrons and holes in these macroporous-mesoporous TiO_(2) microspheres is also suppressed.The hierarchical porous C/S/N-TiO_(2) microspheres show high visible-light catalytic efficiency and excellent cycling stability to degrade RhB dye.Xiaoling Cui Huarong Liu Xingyuan Zhang Hewen Liu 2021Chinese Chemical Letters2021,32,3:1
7Hyperbranched polymers with maleic functional groups as radical crosslinkers显示文摘Hewen Liu Carl-Eric Wilen 2001Journal of Polymer Science PartA: Polymer Chemistry2001,39,:1
8Magnetic Force Microscopy Applied in Magnetic Data Storage Technology显示文摘Koblischkal M R Hewenerl B Hewener B 2003Appl Phys A2003,76,:1
9Photofluorescence of hyperbranched poly(phenylene sulfide)显示文摘Ranglei X Hewen L Wenfang S 2006Journal of Polymer Science:Part B Polymer Physics2006,44,:1
10Effect of core structure on the fluorescence properties of hyperbranched poly(phenylene sulfide)显示文摘Ranglei X Hewen L Shiyong L 2008Journal of Applied Polymer Science2008,107,:1
11Effect of core structure on the fluorescence properties of hyperbranched poly ( phenylene sulfide ) 显示文摘Ranglei X Hewen L Shiyong L 2008Journal of Applied Polymer Science2008,107,:1
12Radical alternating copolymerizatioa: a strategy for hyperbranched materials显示文摘Liu Hewen Jan H Nasman Mikael Skrifvars 2000Journal of Polymer Science Part A: Polymer Chemistry2000,38,:1
13Optimized design and experiment of spiral-type intra-row weeding actuator for maize(Zea mays L.)planting显示文摘Mechanical weeding not only avoids crop herbicide residue but also protects the ecological environment.Compared with mechanical inter-row weeding,mechanical intra-row weeding needs to avoid crop plants,which is conducive to causing a higher rate of seedling damage.In order to realize maize(Zea mays L.)intra-row weeding,a maize intra-row weeding mechanism was designed in this study.The mechanism can detect maize seedlings by infrared beam tube,then a sliding-cutting bevel tool moves spirally amid maize seedlings,so as to eradicate intra-row weeds.A field experiment was conducted under the following experimental conditions:the bevel tool rotation speed was 800-1400 r/min,the mechanism forward speed was 4-7 km/h,and the bevel tool depth was 2-14 cm,the experimental results illustrated that the mechanism’s average weeding rate and seedling damage rate were 95.8%and 0.6%,respectively.The variance analysis showed that the primary and secondary factors that affecting the weeding rate and seedling damage rate were the same,which were bevel tool rotation speed,mechanism forward speed,bevel tool depth in soil in a descending order according to the significances.The result of the field experiment may provide a reference for intra-row weeding device design.Honglei Jia Binglong Gu Zhongyang Ma Huili Liu Gang Wang Mingwei Li Hewen Tan 2021International Journal of Agricultural and Biological Engineering2021,14,6:1
14Post-tensioned and shaped hypar space trusses 显示文摘Li Hewen L C Schmidt 1997Journal of Structural Engineering ASCE1997,123,2:1
15Efficient photoreduction strategy for uranium immobilization based on graphite carbon nitride/activated carbon nanocomposites显示文摘Uranium removal from aqueous solutions using environmentally friendly photocatalytic technology is a novel approach for resource recovery.Herein,carbon nitride/activated carbon composite materials(CN/AC)were investigated for U(Ⅵ)reduction under visible light.An exceptional boost in photocatalytic activity was observed for CN/AC composites(up to 70 times over the conventional bulk g-C_(3)N_(4)).The strong interactive conjugatedπ-bond structure between g-C_(3)N_(4) and AC accelerated the migration of carriers and then prolonged the electron lifetime.CN/AC composites exhibited excellent compatibility with different water substrates and were resilience to a wide range of p H changes and abundant competitive anions/cations.Quenching experiments and electron microscopy characterization indicated that U(VI)was reduced by photogenerated electrons and deposited on the edge of CN/AC composites.The low-cost,high-performance carbon-based composite material proposed in this work is a potential candidate for the efficient treatment of radioactive wastewater.Shuyang Li Zhiwei Niu Duoqiang Pan Zhenpeng Cui Hewen Shang Jie Lian Wangsuo Wu 2022Chinese Chemical Letters2022,33,7:1
16Construction and characterization of a recombinant fowlpox virus containing HIV-1 multi-epitope-p24 chimeric gene in mice显示文摘The epidemic of HIV/AIDS is sweeping across the world. It is of great importance to figure out new ways to curb this disease. Epitope-based vaccine is one of these solutions. In this study, a chimeric gene was obtained by combination of a designed HIV-1 multi-epitope gene (MEG) and HIV-1 p24 gene. A re- combinant plasmid pUTA2-MEGp24 was then constructed by inserting MEGp24 gene into the down- stream of the promoter (ATI-P7.5×20) of fowlpox virus (FPV) transfer vector pUTA2. The recombinant plasmid and wild-type FPV 282E4 strain were then co-transfected into CEF cells and homologous re- combination occurred. A recombinant virus expressing HIV-1 protein MEGp24 was screened by ge- nome PCR and Western blot assay. Large scale preparation and purification of the recombinant fowl- pox virus (rFPV) were then carried out. BALB/c mice were immunized intramuscularly with the rFPV for three times on day 0, 14 and 42. Mice were executed and sampled one week after the third inoculation. Anti-HIV-1 antibody in serum and Th1 cytokines in the supernatant of cultured spleen cells were as- sayed by ELISA. The count of T lymphocyte subsets and the CTL activity of spleen lymphocytes were analyzed by flow cytometry and lactate dehydrogenase (LDH) release assay, respectively. The results showed that HIV-1 specific antibody in serum and increased T lymphocyte subsets (CD4+ T, CD8+ T) were detected in the immunization group. CTL target-killing activity and higher secretion of Th1 cyto- kines (IFN-γ and IL-2) of spleen lymphocytes stimulated by H-2d-restricted CTL peptide were observed in immunized mice. We concluded that the rFPV may induce HIV-1 specific immunity especially cellular immunity in mice.ZHANG LiShu JIN NingYi SONG YingJin WANG Hong MA HeWen LI ZiJian JIANG WenZheng 2007Science China(Life Sciences)2007,50,2:1
17Hyperbranched polymers with functional groups as radical crosslinkers显示文摘Liu Hewen Wilen Carl-Eric 2001Journal of Polymer Science Part A: Polymer Chemistry2001,39,:1
18A Novel Subspace Approach for Hyperbolic Mobile Location显示文摘CHEN Zhangxin WAN Qun WEI Hewen YANG Wanlin 2009Chinese Journal of Electronics2009,18,3:1
19Shape formation o{ deployable metal domes 显示文摘SCHMIDT L C LI Hewen 1995Intenational Journal of Space Structures1995,10,4:1
20A novel weighted multidi- mensional sealing analysis for time-of-arrival-basedmo- bile location显示文摘7/el Hewen Wan Quan 2008IEEE Transactions on Signal Process- ing2008,56,7:1
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