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Influence of a New Nano-PE-film on the Greenhouse Environmental Factors 被引量:1
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作者 陈园园 周宁琳 +6 位作者 李文秀 王佳 朱晓玲 胡锦阳 陈媛媛 冯伟民 徐磊 《Agricultural Science & Technology》 CAS 2015年第3期417-419,共3页
[Objective] This study was to evaluate the impact of a new controlled release anti-drip nano-PE-film (CRANPF) on greenhouse environmental factors. [Method] CRANPF and conventional anti-drip PE film (CLAPF) were co... [Objective] This study was to evaluate the impact of a new controlled release anti-drip nano-PE-film (CRANPF) on greenhouse environmental factors. [Method] CRANPF and conventional anti-drip PE film (CLAPF) were compared in terms of air temperature, light intensity and CO2 concentration by the leafy agriculture greenhouse intelligent monitoring system. [Result] Compared to CLAPF, the air temperature rose slower in CRANPF during hot weather and had better photosynthesis efficiency. [Conclusion] Compared with ODLAPF, CRANPF has better perfor- mance and more extensive application prospects. 展开更多
关键词 Controlled release anti-drip nano-PE-film (CRANPF) Light intensity Air temperature CO2 concentration
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Slope Debris Flows in the Wenchuan Earthquake Area 被引量:13
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作者 LI Yanfu WANG Zhaoyin +1 位作者 SHI Wenjing WANG Xuzhao 《Journal of Mountain Science》 SCIE CSCD 2010年第3期226-233,共8页
Avalanches and landslides,induced by the Wenchuan Earthquake on May 12,2008,resulted in a lot of disaggregated,solid material on slopes that could be readily mobilized as source material for debris flows.Rainstorms tr... Avalanches and landslides,induced by the Wenchuan Earthquake on May 12,2008,resulted in a lot of disaggregated,solid material on slopes that could be readily mobilized as source material for debris flows.Rainstorms triggered numerous slope debris flows with great damage to highways and rivers over the subsequent two years.Slope debris flows(as opposed to channelized debris flows) are defined as phenomena in which high-concentration mixtures of debris and water flow down slopes for short distances to highways and river banks.Based on field investigations and measurements of 19 slope debris flows,their main characteristics and potential mitigation strategies were studied.High rainfall intensity is the main triggering factor.Critical rainfall intensities for simultaneous occurrence of single,several and numerous slope debris flow events were 20 mm/day,30mm/day,and 90 mm/day,respectively.Field investigations also revealed that slope debris flows consist of high concentrations of cobbles,boulders and gravel.They are two-phase debris flows.The liquid phase plays the role of lubrication instead of transporting medium.Solid particles collide with each other and consume a lot of energy.The velocities of slope debris flows are very low,and their transport distances are only several tens of meters.Slope debris flows may be controlled by construction of drainage systems and by reforestation. 展开更多
关键词 Slope debris flow rainfall intensity Wenchuan Earthquake LANDSLIDE AVALANCHE
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Cloud microphysical differences with precipitation intensity in a torrential rainfall event in Sichuan, China 被引量:5
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作者 HUANG Yong-Jie CUI Xiao-Peng WANG Ya-Ping 《Atmospheric and Oceanic Science Letters》 CSCD 2016年第2期90-98,共9页
High-resolution data of a torrential rainfall event in Sichuan, China, simulated by the WRF model, were used to analyze the cloud microphysical differences with precipitation intensity. Sixhourly accumulated rainfall ... High-resolution data of a torrential rainfall event in Sichuan, China, simulated by the WRF model, were used to analyze the cloud microphysical differences with precipitation intensity. Sixhourly accumulated rainfall was classified into five bins based on rainfall intensity, and the cloud microphysical characteristics and processes in different bins were studied. The results show that:(1) Hydrometeor content differed distinctly among different bins. Mixing ratios of cloud water, rain water, and graupel enhanced significantly and monotonously with increasing rainfall intensity. With increasing precipitation intensity, the monotonous increase in cloud water number concentration was significant. Meanwhile, number concentrations of rain water and graupel increased at first and then decreased or increased slowly in larger rainfall bins.(2) With precipitation intensity increasing, cloud microphysical conversion processes closely related to the production of rainwater, directly(accretion of cloud water by rain(QCLcr) and melting of graupel(QMLgr)) or indirectly(water vapor condensation and accretion of cloud water by graupel), increased significantly.(3) As the two main sources of rainwater, QCLcrincreased monotonously with increasing precipitation intensity, while QMLgr increased slowly, even tending to cease increasing in larger rainfall bins. 展开更多
关键词 cloud microphysics cloud microphysical processes torrential rainfall numerical simulation
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Modelling and Fixed Bed Column Adsorption of Cr(Ⅵ) onto Orthophosphoric Acid-activated Lignin 被引量:3
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作者 Ahmad B.Albadarin Chirangano Mangwandi +3 位作者 Ala'a H.Al-Muhtaseb Gavin M.Walker Stephen J.Allen Mohammad N.M.Ahmad 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第3期469-477,共9页
The advantage of using an available and abundant residual biomass, such as lignin, as a raw material for activated carbons is that it provides additional economical interest to the technical studies. In the current in... The advantage of using an available and abundant residual biomass, such as lignin, as a raw material for activated carbons is that it provides additional economical interest to the technical studies. In the current investigation, a more complete understanding of adsorption of Cr(VI) from aqueous systems onto HaPO4-acid activated lignin has been achieved via microcolumns, which were operated under various process conditions. The practice of using microcolumn is appropriate for defining the adsorption parameters and for screening a large number of poten- tial adsorbents. The effects of solution pH (2-8), initial metal ion concentration (0.483-1.981 mmol.L-1), flow rate (1.0-3.1 cm3-min-1), ionic strength (0.01-0.30 mmol-L-1) and adsorbent mass (0.11 0.465 g) on Cr(VI) adsorption were studied by assessing the microcolmnn breakthrough curve. The microcolumn data were fitted by the Thomas model, the modified Dose model and the BDST model. As expected, the adsorption capacity increased with initial Cr(VI) concentration. High linear flow rates, pH values and ionic strength led to early breakthrough of Cr(VI). The model constants obtained in this study can be used for the design of pilot scale adsorption process. 展开更多
关键词 activated carbon LIGNIN hexavalent chromium ADSORPTION fixed bed column
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Effects of Illumination Intensity, 5-aminolevulinic Acid Concentration and Their Interaction on Chlorophyll Fluorescence Parameters and Yield of Summer Maize
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作者 韩玉龙 李慧 +5 位作者 苗玉红 汪强 王宜伦 王祎 谭金芳 韩燕来 《Agricultural Science & Technology》 CAS 2013年第5期757-762,805,共7页
[Objective] This study aimed to investigate the influence of illumination intensity, 5-aminolevulinic acid (ALA) concentration and their interaction on chlorophyll fluorescence parameters and yield of summer maize. ... [Objective] This study aimed to investigate the influence of illumination intensity, 5-aminolevulinic acid (ALA) concentration and their interaction on chlorophyll fluorescence parameters and yield of summer maize. [Method] Two illumination intensity levels and five ALA concentrations were applied in the experiment using 2x5 completely balanced program. The two illumination intensity levels were natural light (So) and 60% shade (SO, and five ALA concentrations were 0, 1, 10, 25 and 50 mg/L. [Result] The relative chlorophyll content of leaf (SPAD), the optimal/maximal quantum yield of PS II (Fv/Fm), the photochemical quenching coefficient (qP), electron transport rate (ETR), grain number per cob and grain weight per cob in $1 treatment were significantly reduced compared with that in So. However, the non- photochemical quenching coefficient (qN) was significantly increased. The responses of these parameters to ALA were different under So and $1 treatments. The SPAD, Fv/Fm, qP, ETR, grain number and grain weight per cob were firstly increased, but then decreased following the raise of ALA concentration, ranging from 0 to 50 mg/L, whereas qN showed opposite trend. The effect of the interaction of illumination in- tensity and ALA concentration on these parameters was significant (P〈0.05). Under natural light, summer maize could obtain higher SPAD, Fv/Fm, qP and ETR and lower qN combined with low concentration of ALA. However, high concentration of ALA was needed under shading to get the same results. [Conclusion] Soaking seed in suitable concentration of ALA can reduce the yield loss of summer maize caused by short-term shading in seedling stage. 展开更多
关键词 Summer maize 5-aminolevulinic acid concentration for soaking seed Chiorophyll fluorescence parameters YIELD
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The Collapse Intensity of Cavities and the Concentration of Free Hydroxyl Radical Released in Cavitation Flow 被引量:3
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作者 张晓冬 付勇 +1 位作者 李志义 赵宗昌 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第4期547-551,共5页
Enhancing the chemical reaction processes by means of the energy released in the collapse of micro bubbles or cavities in the cavitation flow is a new research area. In the previous work, a new approach of measuring c... Enhancing the chemical reaction processes by means of the energy released in the collapse of micro bubbles or cavities in the cavitation flow is a new research area. In the previous work, a new approach of measuring concentration of free hydroxyl radicals induced in cavitation flow by using methylene blue as the indicator was developed and used to study concentration of free radical induced in Venturi cavitation flow under various experimental conditions. In the present research, the radial evolution of a cavity bubble and the corresponding collapse pressure in sonic cavitation field are obtained by solving three different bubble dynamics equations: Rayleigh equation, Rayleigh-Plesset equation and Gilmore equation. By comparing with the experimental data on the radial evolution of a cavity bubble in the literature, it is found that the predicted results by the Gilmore equation, which takes account of the compressibility of fluid in addition to the viscosity and interfacial tension, agree with the experimental ones better than those by other two equations. Moreover, the theoretically predicted collapse pressures are consistent with the concentration of the free hydroxyl radical induced in the experimental venture. Thus, the concentration of the liberated free hydroxyl radical not only influences the reaction rate but also is used as an available parameter for measuring collapse intensity of cavities. 展开更多
关键词 hydrodynamic cavitation collapse pressure numerical simulation free hydroxyl radical
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Stormwater Runoff Pollution in a Rural Township in the Hilly Area of the Central Sichuan Basin,China 被引量:1
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作者 LUO Zhuanxi WANG Tao +2 位作者 GAO Meirong TANG Jialiang ZHU Bo 《Journal of Mountain Science》 SCIE CSCD 2012年第1期16-26,共11页
Stormwater runoff in rural townships has a high potential for water quality impairment but little information is available on strormwater runoff pollution from rural townships.To investigate the characteristics of run... Stormwater runoff in rural townships has a high potential for water quality impairment but little information is available on strormwater runoff pollution from rural townships.To investigate the characteristics of runoff pollution in a rural township,a catchment(2.32 ha) in Linshan Township,Sichuan,China was selected to examine runoff and quality parameters including precipitation,flow rate,and total nitrogen(TN),dissolved nitrogen(DN),total phosphorus(TP),dissolved phosphorus(DP),particulate phosphorus(PP),chemical oxygen demand(COD) and suspended solid(SS) in 12 rainfall events occurring between June 2006 and July 2007.Results show that the annual pollutant loads were 47.17 kg ha-1 for TN,6.64 kg ha-1 for TP,1186 kg ha-1 for COD,and 4297 kg ha-1 for SS.DN and PP were the main forms of nitrogen and phosphorus in stormwater runoff.TP,COD and SS showed medium mass first flushes,in which nearly 40% of the total pollutant masses were transported by the first 30% of total flow volume.The peak of pollutant concentration appeared before the peak of runoff due to the first flush of accumulative pollutants in impervious areas and drainage ditches.The EMC values of TN,TP,DN and PP were negatively correlated to the maximum rainfall intensity,precipitation,total flow volume,and runoff duration(P<0.05,n=12),while EMC of COD and SS were not related to any rainfall characteristics.The FF30(FF,First Flush) for TN,TP,COD and SS were positively correlated to the maximum rainfall intensity(P<0.05,n=12),and TP was also positively correlated to the average rainfall intensity(P<0.05,n=12),indicating that the magnitude of first flush increased with the rainfall intensity in the Linshan Township. 展开更多
关键词 First flush Pollutant EMC Storm water Runoff Load
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Intraseasonal oscillation intensity over the western North Pacific:Projected changes under global warming 被引量:1
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作者 Yi Fan Ke Fan Zhiqing Xu 《Atmospheric and Oceanic Science Letters》 CSCD 2021年第4期1-6,共6页
The 30-60-day intraseasonal oscillation(ISO) and 10-20-day ISO are two dominant oscillation modes over the western North Pacific during boreal summer.With daily data derived from eight CMIP5 models,changes of the ISO ... The 30-60-day intraseasonal oscillation(ISO) and 10-20-day ISO are two dominant oscillation modes over the western North Pacific during boreal summer.With daily data derived from eight CMIP5 models,changes of the ISO intensities are projected under the 1.5 and 2.0℃ global warming levels under the Representative Concentration Pathway(RCP) 4.5 and RCP8.5 scenarios.Most of the models agree that the ISO intensities increase along a belt region from the south Indochina Peninsula(ICP) to the east to the Philippines.The variation pattern shows little difference between different warming levels or scenarios.Results indicate that the spatial distribution of ISO anomalies is related with the variation of background fields.Enriched lower-level humidity and moist static energy favor the intensity increases of ISOs,which are projected to be larger over the whole western North Pacific,with the most conspicuous changes located over the east to the Philippines for humidity but over the south of the ICP for moist static energy.In contrast,the ISOs over the west to Indonesia and northeast to the Philippines decrease,which is consistent with the local descending motions. 展开更多
关键词 Intraseasonal oscillation intensity Representative concentration pathway 1.5 and 2.0℃ global warming Western North Pacific
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职业病危害预评价逻辑结构优化研究
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作者 袁智 《工业安全与环保》 2018年第8期51-53,106,共4页
针对目前大部分中小企业提交的可研报告基本上没提及防护设施设置方面内容的现状,结合预评价报告编制相关技术要求,研究利用类比检测数据有效推断评价项目作业岗位3种不同情况下的职业病危害因素预期浓度(强度)逻辑关系,并对职业病危害... 针对目前大部分中小企业提交的可研报告基本上没提及防护设施设置方面内容的现状,结合预评价报告编制相关技术要求,研究利用类比检测数据有效推断评价项目作业岗位3种不同情况下的职业病危害因素预期浓度(强度)逻辑关系,并对职业病危害因素识别与评价、防护设施分析评价的逻辑结构进行重新优化调整。结果表明:评价逻辑重构后,类比检测数据与拟建项目各岗位的接触浓度(强度)更具可比性;防护设施分析评价的范围扩大到补充措施中,使得防护设施评价内容更具体、更全面、更能真实反映全部防护设施的合理性和有效性情况。评价逻辑重新优化后评价报告结构更严谨、条理更清晰、逻辑更严密,更具客观说服力。 展开更多
关键词 职业病危害 预评价 危害因素 预期浓度(强度) 逻辑结构
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Study on a Novel Disphase Supplying Supported Liquid Membrane for Transport Behavior of Divalent Nickel Ions
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作者 裴亮 王理明 +1 位作者 郭维 赵楠 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第4期633-640,共8页
A novel d!sphase supplying supported liquid membrane (DSSLM), containing supplying feed phase andsupplying stripping phase tor transport behavior ot NI(Ⅱ), have been studied. The supplying supported feed phase in... A novel d!sphase supplying supported liquid membrane (DSSLM), containing supplying feed phase andsupplying stripping phase tor transport behavior ot NI(Ⅱ), have been studied. The supplying supported feed phase included feed solution and di(2-ethyhexyl) phosphoric acid (HDEHP) as the carrier in kerosene, and supplying stripping phase included HDEHP as the cartier in kerosene and HC1 as the stripping agent. The effects of volume ratio of membrane solution to feed solution (O/F), pH, initial concentration of Ni(Ⅱ) and ionic strength in the feedsolution, volume ratio of membrane solution to stripping solution (O/S), concentration of H2SO4 solution, HDEHP concentration in the supplying stripping phase on transport of Ni(/I), the advantages of DSSLM compared to the traditional supported liquid membrane (SLM), the system stability, the reuse of membrane solution and the reten- tion of membrane phase were studied. Experimental results indicated that the optimum transpgrt of Ni(Ⅱ) was oh-tained when H2SO4 concentration was 2.00 mol'L-', HDEHP concentration was 0.120 mol·L-1, and O/S was 4· 1 in the supplying stripping phase, O/F was 1 : 10 and pH was 5.20 in the supplying feed phase. The ionic strength in supplying feed phase had no obvious effect on transport of Ni(Ⅱ). When initial Ni(Ⅱ) concentration was 2.00x 10-4 mol/L, the transport percentage of Ni(Ⅱ) was up to 93.1% in 250 min. The kinetic equation was deduced in terms of the law of mass diffusion and the interface chemistry. 展开更多
关键词 disphase supplying supported liquid membrane organic phosphonic acid supplying feed phase sup-plying stripping phase nickel ion
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Numerical analysis of aerated heap bioleaching with variable irrigation and aeration combinations 被引量:1
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作者 HUANG Ming-qing WU Ai-xiang 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第5期1432-1442,共11页
Forced aeration is an effective way to accelerate the heap bioleaching process.To reveal the effects of different irrigation and aeration combinations on bioleaching performance of copper sulfides,numerical simulation... Forced aeration is an effective way to accelerate the heap bioleaching process.To reveal the effects of different irrigation and aeration combinations on bioleaching performance of copper sulfides,numerical simulations with COMSOL were carried out.Results showed the oxygen concentration is the highest at the bottom with forced aeration,the airflow transports spherically from the aeration pipeline to the slope,and the horizontal diffusion distance is further than vertical value.When the irrigation-to-aeration ratio is higher,the average heap temperatures are mainly decided by aeration rates;otherwise,temperature distributions are the equilibrium of mineral reaction heat,the livixiant driven heat and the airflow driven heat.When the aeration rate is higher than 0.90 m3/(m2·h),oxygen concentration is no longer a limiting factor for mineral dissolution.Additionally,on the premise of sufficient oxygen supply,Cu recovery rate is higher at the bottom with low irrigation rate;while it is higher at upper regions with high irrigation rate.The numerical analysis uncovered some insights into the dynamics and thermodynamics rules in bioleaching of copper sulfides with forced aeration. 展开更多
关键词 forced aeration irrigation-to-aeration ratio oxygen concentration temperature distribution copper leaching rate
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Electrokinetic phenomena of poly(vinyl butyral) hollow fiber membranes in different electrolyte solutions
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作者 漆静 王永前 邱运仁 《Journal of Central South University》 SCIE EI CAS 2013年第6期1490-1495,共6页
The streaming potential of poly(vinyl butyral) (PVB) hollow fiber membrane was studied in different electrolyte solutions (including NaCl, KCl, CaCl2 and MgCl2), the effects of ionic strength, ion valence and pH... The streaming potential of poly(vinyl butyral) (PVB) hollow fiber membrane was studied in different electrolyte solutions (including NaCl, KCl, CaCl2 and MgCl2), the effects of ionic strength, ion valence and pH value on the streaming potential (SP) of the membrane were investigated. The zeta potentials and surface charge densities of the membrane were estimated on the basis of Helmholtz-Smoluchowski equation and Gouy-Chapmann theory. The results show that the PVB membrane has a weak negative charge due to the specific adsorption of ions. Moreover, the streaming potential, the zeta potential and the surface charge density of the membrane depend strongly on the salt concentration and the type and valence of ions. The iso-electric point (IEP) of the PVB membrane is arotmd 3.0 in the monovalent media (NaC1 and KC1) and 3.5 in divalent electrolytes (CaCl2 and MgCl2). A few retentions were obtained for PVB membrane in low concentration solutions. This result verifies that the negative charged membrane surface can reject inorganic solutes by means of electrostatic repulsion effect even though the size of membrane pores is much larger than the size of salts. 展开更多
关键词 streaming potential zeta potential poly(vinyl butyral) hollow fiber membrane
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The compressive strength experimental study of cemented soil under H2SO4 corrosive in earlier period
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作者 HAN Peng-ju BAI Xiao-hong HAO Hai-yan 《Journal of Civil Engineering and Architecture》 2009年第3期54-58,共5页
In order to simulate and study the erosion effect process such as the changes of corrosive depth and unconfined compression strength of cemented soil sample in earlier period from 0 day to 60 days, a series of tests i... In order to simulate and study the erosion effect process such as the changes of corrosive depth and unconfined compression strength of cemented soil sample in earlier period from 0 day to 60 days, a series of tests including unconfined compressive tests, measuring the blocks' sizes, and taking photos, are conducted on the cemented soil blocks which were cured in different concentrations of H2SO4 solutions. The results of tests show that the corrosive depth is increasing and the unconfined compression strength is decreasing with the increase of H2SO4 solution concentration at the same erosion time, and the corrosive degree is increasing with the corrosive time. In the earlier state, the corrosive effect is serious, but the effect becomes slow in the later state in the same concentrated H2SO4 solution. After take statistics the date, a coefficient a is put forward to predict the reduction of the compressive strength of cemented soil in various concentration of H2SO4 solution, which could be used in practical design. 展开更多
关键词 cemented soil corrosive depth unconfined compression strength reduced coefficient
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企业扩能项目职业病危害预评价方法探讨
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作者 樊玉芳 何玉红 +2 位作者 何虎鹏 何小刚 寇振霞 《工业卫生与职业病》 CAS CSCD 北大核心 2009年第1期35-37,共3页
通过对某厂房内扩能项目的职业病危害预评价,探讨原有生产线作为类比的合理性,为今后类似的建设项目职业病危害评价工作提供参考。我们对原硝化工房进行现场职业卫生调查及职业病危害因素检测,预测扩能后的职业危害程度,并在项目竣工后... 通过对某厂房内扩能项目的职业病危害预评价,探讨原有生产线作为类比的合理性,为今后类似的建设项目职业病危害评价工作提供参考。我们对原硝化工房进行现场职业卫生调查及职业病危害因素检测,预测扩能后的职业危害程度,并在项目竣工后予以实测验证。结果显示,通过对扩能前后职业病危害因素的检测数据统计分析,噪声预测值与扩能后厂房内实际检测值比较,差异无统计学意义;毒物浓度不变或有所降低。提示,对在同一厂房内的扩能项目,选择已有部分作为类比对象是可行的。 展开更多
关键词 炸药厂 职业病危害评价 浓度(强度) 效应叠加
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Response of peptide intensity to concentration in ESI–MS-based proteome 被引量:1
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作者 LU WenYuan YIN XueFei +2 位作者 LIU XiaoHui YAN GuoQuan YANG PengYuan 《Science China Chemistry》 SCIE EI CAS 2014年第5期686-694,共9页
High-throughput quantification with label-free methods has received considerable attention in electrospray ionization(ESI)-mass spectrometry(MS),but the manner by which MS signals respond to peptide concentration rema... High-throughput quantification with label-free methods has received considerable attention in electrospray ionization(ESI)-mass spectrometry(MS),but the manner by which MS signals respond to peptide concentration remains unclear in proteomics.We developed a new mathematical formula to describe the intrinsic log-log relationship between the MS intensity response and peptide concentration in an analytical ESI process.Experimental results showed that the calibration curve is fairly fit to the log-log formula with a linear dynamic range of approximate four to five orders of magnitude.However,we found that the ionization of analytical peptides can be severely suppressed by coexisting matrix peptides,such that the calibration curve can be poorly leveled off on both ends.Our study suggests that the interferences from coexisting matrix peptides should be reduced in the ESI process to use the log-log calibration curve successfully for the high-throughput quantification. 展开更多
关键词 peptide quantification ESI-MS peptide intensity peptide concentration interference
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Theoretical relationships between first flush of roof runoff and influencing factors 被引量:2
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作者 Biao WANG Tian L 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第5期746-757,共12页
Considering the short length of building roofs, a theoretical analysis of the first flush of roof runoff was conducted based on the kinematic wave and pollutant erosion equations. This mathematical derivation with ana... Considering the short length of building roofs, a theoretical analysis of the first flush of roof runoff was conducted based on the kinematic wave and pollutant erosion equations. This mathematical derivation with analytical solutions predicts pollutant mass first flush (MFF), mean concentration of initial runoff (MCIF), mean concentration of roof runoff (MCRR) with diversion of initial portion and residual mass available on the bed surface (RS) after the entire runoff under the condition of con-stant excess rainfall. And the effects of the associated influencing factors (roof length, roof gradient, roof surface roughness, rainfall intensity, rainfall duration, and erosion coefficients) on them were discussed while the values of parameters referred to the previous studies. The results showed that for roofs whose length is shorter than 20 m, both the increase in roof length and roof gradient and the decrease in roof surface roughness result in larger MFF and MCIF and smaller MCRR and RS, which is beneficial to water reuse and pollution reduction. The theoretical relationship between the first flush and the influencing factors may aid the planning and design of roof in terms of rainwater utilization or diffuse pollution control. 展开更多
关键词 Roof runoff Kinematic wave equation Pollutant erosion equation First flush
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Epidemiological and antibiotic resistant study on extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae in Zhejiang Province
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作者 俞云松 周伟琳 +2 位作者 陈亚岗 丁永祥 马亦林 《Chinese Medical Journal》 SCIE CAS CSCD 2002年第10期39-42,146,共5页
To investigate the epidemiological status of extended spectrum β lactamase (ESBL) producing Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) and the drug resistance profiles of such organisms ... To investigate the epidemiological status of extended spectrum β lactamase (ESBL) producing Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) and the drug resistance profiles of such organisms Methods A total of 282 clinical isolates of E coli and 180 of K pneumoniae were collected from different districts of Zhejiang Province Inhibitor potentiated broth dilution tests were performed for detecting extended spectrum β lactamases Etests were performed to detect the drug resistance of these strains against nine commonly used antibiotics Results The prevalence of extended spectrum β lactamases in E coli and K pneumoniae was 34 0% and 38 3%, respectively The average prevalence of extended spectrum β lactamases in E coli and K pneumoniae was 35 7% The resistance prevalence of extended spectrum β lactamase producing strains to ceftazidime and cefotaxime was 40% and 26% respectively, so were those to cefepime, cefoxitin, piperacillin tazobactam, cefoperazone sulbactam, amikacin and ciprofloxacin All these strains were sensitive to imipenem Conclusion The results in this study showed that the prevalence of extended spectrum β lactamases was high, while extended spectrum β lactamase producing strains were resistant to most antimicrobial agents except imipenem 展开更多
关键词 extended spectrum β lactamases · inhibitor potentiated broth dilution test · E test
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Defects production and mechanical properties of typical metal engineering materials under neutron irradiation
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作者 LIU Jian TANG XiaoBin +3 位作者 CHEN FeiDa HUANG Hai LI Huan YANG YaHui 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2015年第10期1753-1759,共7页
Maintaining the safety and reliability of nuclear engineering materials under a neutron irradiation environment is significant. Atomic-scale simulations are conducted to investigate the mechanism of irradiation-induce... Maintaining the safety and reliability of nuclear engineering materials under a neutron irradiation environment is significant. Atomic-scale simulations are conducted to investigate the mechanism of irradiation-induced vacancy formation in CLAM, F82 H and α-Fe with different neutron energies and objective laws of the effect of vacancy concentration on mechanical properties of α-Fe. Damage of these typical metal engineering materials caused by neutrons is mainly displacement damage, while the displacement damage rate and the non-ionizing effect of neutrons decrease with the increase of neutron energy. The elastic modulus, yield strength, and ultimate strength of α-Fe are in the order of magnitude of GPa. However, the elastic modulus is not constant but decreases with the increase of strain at the elastic deformation stage. The ultimate strength reaches its maximum value when vacancy concentration in α-Fe is 0.2%. On this basis, decreasing or increasing the number of vacancies reduces the ultimate strength. 展开更多
关键词 Monte Carlo molecular dynamics neutron irradiation displacement damage rate mechanical properties
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Soil Respiration, Microbial Biomass and Nutrient Availability in Soil After Addition of Residues with Adjusted N and P Concentrations 被引量:3
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作者 Trung Ta NGUYEN Petra MARSCHNER 《Pedosphere》 SCIE CAS CSCD 2017年第1期76-85,共10页
Microbial activity and nutrient release are known to be influenced by organic matter properties,but it is difficult to separate the effect of C/N ratio from that of C/P ratio because in most plant residues both ratios... Microbial activity and nutrient release are known to be influenced by organic matter properties,but it is difficult to separate the effect of C/N ratio from that of C/P ratio because in most plant residues both ratios are either high or low.An incubation experiment was conducted to investigate the effects of reducing the C/N and C/P ratios of slowly decomposable plant residues(young eucalyptus leaves,mature wheat straw,and sawdust) to those of rapidly decomposable residues(young kikuyu shoots) on soil respiration,microbial biomass,and N and P availability.The C/N and C/P ratios of the former were adjusted to 15 and 89,respectively,by adding N as(NH_4)_2SO_4,P as KH_2PO_4 or both and residues were added at 10 g C kg-1 to a silt loam.Soil respiration was measured over21 d;microbial biomass C(MBC) and available N and P were measured on days 0,7,and 21.Compared to the unamended soil,addition of kikuyu increased cumulative respiration 20-fold,MBC concentration 4 to 8-fold,and available P concentration up to4-fold,whereas the increase in available N concentration was small and transient.Cumulative respiration and MBC concentration were low in the sawdust-amended soil and were not influenced by reducing the C/N and C/P ratios.Cumulative respiration with original wheat and eucalyptus was 30%-40%of that with kikuyu.Reducing the C/N ratio alone or both C/N and C/P ratios increased cumulative respiration and MBC concentration 2-fold compared to the original wheat and eucalyptus,whereas reducing the C/P ratio had little effect.Throughout the experiment,the available N concentration after addition of residues with reduced C/N ratio increased in the following order of eucalyptus < wheat < sawdust.By independently lowering the C/N and C/P ratios,microbial activity was more limited by C and N than P.However,lowering the C/N ratio of very slowly decomposable sawdust had no effect on soil respiration and MBC concentration,suggesting that other properties such as concentration of poorly decomposable C compounds limited decomposition. 展开更多
关键词 C/N ratio C/P ratio microbial activity nutrient immobilisation nutrient mineralisation
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Enhancement of solubility and mass transfer coefficient of salicylic acid through hydrotropy
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作者 S.THENESHKUMAR D.GNANAPRAKASH N.NAGENDRA GANDHI 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第5期739-745,共7页
This study deals with the effect of hydrotropes on the solubility and mass transfer coefficient of salicylic acid. The solubility and mass transfer studies were performed using the hydrotropes, i.e., sodium acetate, s... This study deals with the effect of hydrotropes on the solubility and mass transfer coefficient of salicylic acid. The solubility and mass transfer studies were performed using the hydrotropes, i.e., sodium acetate, sodium salicylate, citric acid, and urea at concentrations of 0-3.0 mol/L and system temperatures of 303-333 K. It was found that the solubility and mass transfer coefficient of salicylic acid increases with increase in hydrotrope concentration and also with system temperature. All hydrotropes used in this work showed an enhancement in solubility and mass transfer coefficient to different degrees. The maximum enhancement factor values were determined for all hydrotropes used in this study. The highest value was 28.08 for solubility studies and 10.42 for mass transfer studies. The performance of hydrotropes was measured in terms of the Setschenow constant (Ks). The highest value observed was 0.696. 展开更多
关键词 Hydrotropy HYDROTROPES SOLUBILIZATION Mass transfer coefficient SEPARATION
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