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Quality Control and Evaluation of the Observed Daily Data in the North American Soil Moisture Database
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作者 Weilin LIAO Dagang WANG +2 位作者 Guiling WANG Youlong XIA Xiaoping LIU 《气象学报:英文版》 SCIE CSCD 2019年第3期501-518,共18页
The North American Soil Moisture Database (NASMD) was initiated in 2011 to assemble and homogenize in situ soil moisture measurements from 32 observational networks in the United States and Canada encompassing more th... The North American Soil Moisture Database (NASMD) was initiated in 2011 to assemble and homogenize in situ soil moisture measurements from 32 observational networks in the United States and Canada encompassing more than 1800 stations. Although statistical quality control (QC) procedures have been applied in the NASMD, the soil moisture content tends to be systematically underestimated by in situ sensors in frozen soils, and using a single maximum threshold (i.e., 0.6 m3 m-3) may not be sufficient for robust QC because of the diverse soil textures in North America. In this study, based on the in situ soil porosity and North American Land Data Assimilation System phase 2 (NLDAS-2) Noah soil temperature, the simple automated QC method is revised to supplement the existing QC approach. This revised QC method is first validated based on the assessment at 78 of the Soil Climate Analysis Network (SCAN) stations where the manually checked data are available, and is then applied to all stations in the NASMD to produce a more strict quality-controlled dataset. The results show that the revised automated QC procedure can flag the spurious and erroneous soil moisture measurements for the SCAN stations, especially for those located in high altitudes and latitudes. Relative to station measurements in the original NASMD, the quality-controlled data show a slightly better agreement with the manually checked soil moisture content. It should be noted that this quality-controlled dataset may be over-flagged for some valid soil moisture measurements due to potential errors of the soil temperature and soil porosity data, and validation in this study is limited by the availability of benchmark soil moisture data. The updated QC and additional validation will be desirable to boost confidence in the product when high-quality data become available in the future. 展开更多
关键词 NORTH AMERICAN SOIL MOISTURE DATABASE (NASMD) quality control SOIL MOISTURE NORTH AMERICAN Land DATA Assimilation System phase 2 (NLDAS-2) SOIL temperature SOIL porosity
添加剂对高水分挤压组织化复合蛋白理化性质的影响 预览
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作者 刘艳香 谭斌 +8 位作者 刘明 田晓红 郑先哲 汪丽萍 吴娜娜 高琨 翟小童 刘金明 孙勇 《农业工程学报》 EI CAS CSCD 北大核心 2019年第1期294-302,共9页
为了改善高水分挤压组织化复合蛋白肉感不强,肉质纹理结构差的问题,该文以小麦蛋白为主要基料,采用双螺杆高水分挤压技术,研究了添加剂对高水分挤压组织化复合蛋白产品特性的改善效果,并探讨了高水分挤压组织化复合蛋白与市场上熟肉制... 为了改善高水分挤压组织化复合蛋白肉感不强,肉质纹理结构差的问题,该文以小麦蛋白为主要基料,采用双螺杆高水分挤压技术,研究了添加剂对高水分挤压组织化复合蛋白产品特性的改善效果,并探讨了高水分挤压组织化复合蛋白与市场上熟肉制品质构特性的差异。结果表明,不同种类添加剂对高水分挤压组织化复合蛋白产品特性的影响呈现差异性,其中,大豆磷脂、卡拉胶加入不利于高水分挤压组织化复合蛋白成型及网络状纤维结构的形成;氯化钠添加0.5%时,可改善其纤维结构,加大添加量,色泽差异较小,组织化度,硬度及咀嚼度呈下降趋势,不利于复合组织化蛋白网络状纤维结构的形成;碳酸氢钠添加0.2%~0.4%时,可改善其品质特性;L-半胱氨酸添加0.03%~0.09%时,其组织化度、硬度、咀嚼度均呈增加趋势,碳酸氢钠、L-半胱氨酸的添加均有利于复合组织化蛋白网络状纤维结构的形成。由各指标相关性评价可知,感官评分、L^*值、组织化度、咀嚼度可作为其代表性评价指标。高水分复合蛋白的微观结构可直观地剖析添加剂对其组织化结构的影响效果。其中,大豆磷脂、卡拉胶加入时均未形成较多的网络状纤维结构。并与市场上熟肉制品的质构存在较大的差异性,其中硬度、弹性、聚结性、咀嚼度明显增加。适量添加氯化钠、碳酸氢钠、L-半胱氨酸,并结合市场上熟肉制品的质构特性,以感官评分、L^*值、组织化度、咀嚼度为评价指标,将为创制肉感较强、具有肉质纹理的仿肉制品提供基础理论依据。 展开更多
关键词 添加剂 组织 水分 高水分挤压技术 组织化蛋白
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滇中高原火后更新森林植物和土壤水分含量的时空格局
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作者 陈丽芳 窦群 +1 位作者 张志明 沈泽昊 《地理学报:英文版》 SCIE CSCD 2019年第7期1179-1192,共14页
Plant moisture content(PMC) is used as an indicator of forest flammability, which is assumed to be affected by climate drought. However, the fire-induced drought stress on PMC and its spatial and temporal variations a... Plant moisture content(PMC) is used as an indicator of forest flammability, which is assumed to be affected by climate drought. However, the fire-induced drought stress on PMC and its spatial and temporal variations are unclear. Based on a parallel monitoring experiment from 2014 to 2015, this study compared the PMCs and soil moisture contents(SMC) at five post-fire sites in central Yunnan Plateau, Southwest China. The number of years since last fire(YSF), season, topographic position, plant species and tissue type(leaf and branch) were selected as causal factors of the variations in PMC and SMC. A whole year parallel monitoring and sampling in the post-fire communities of 1, 2, 5, 11 and 30 YSF indicated that drought stress in surface soils was the strongest in spring within the first 5 years after burning, and the SMC was regulated by topography, with 64.6% variation in soil moisture accounted for by YSF(25.7%), slope position(22.1%) and season(10.8%). The temporal variations of PMC and SMC differed at both interannual and seasonal scales, but the patterns were consistent across topographic positions. PMC differed significantly between leaves and branches, and among three growth-forms. The mean PMC was lower in broad-leaved evergreen species and higher in conifer species. Season and soil temperature were the primary determinants of PMC, accounting for 19.1% and 8.3% of variation in PMC, respectively. This indicated phenology-related growth rather than drought stress in soil as the primary driver of seasonal changes in PMC. The significant variations of PMC among growth forms and species revealed that seasonal soil temperature change and dominant species in forest communities are useful indicators of fire risk assessment in this region. 展开更多
关键词 plant MOISTURE CONTENT SOIL MOISTURE CONTENT TOPOGRAPHY season SOIL temperature year since last fire drought stress
Remotely sensed estimation and mapping of soil moisture by eliminating the effect of vegetation cover 预览
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作者 WU Cheng-yong CAO Guang-chao +6 位作者 CHEN Ke-long E Chong-yi MAO Ya-hui ZHAO Shuang-kai WANG Qi SU Xiao-yi WEI Ya-lan 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第2期316-327,共12页
Soil moisture(SM), which plays a crucial role in studies of the climate, ecology, agriculture and the environment, can be estimated and mapped by remote sensing technology over a wide region. However, remotely sensed ... Soil moisture(SM), which plays a crucial role in studies of the climate, ecology, agriculture and the environment, can be estimated and mapped by remote sensing technology over a wide region. However, remotely sensed SM is constrained by its estimation accuracy, which mainly stems from the influence of vegetation cover on soil spectra information in mixed pixels. To overcome the low-accuracy defects of existing surface albedo method for estimating SM, in this paper, Qinghai Lake Basin, an important animal husbandry production area in Qinghai Province, China, was chosen as an empirical research area. Using the surface albedo computed from moderate resolution imaging spectroradiometer(MODIS) reflectance products and the actual measured SM data, an albedo/vegetation coverage trapezoid feature space was constructed. Bare soil albedo was extracted from the surface albedo mainly containing information of soil, vegetation, and both albedo models for estimating SM were constructed separately. The accuracy of the bare soil albedo model(root mean square error=4.20, mean absolute percent error=22.75%, and theil inequality coefficient=0.67) was higher than that of the existing surface albedo model(root mean square error=4.66, mean absolute percent error=25.46% and theil inequality coefficient=0.74). This result indicated that the bare soil albedo greatly improved the accuracy of SM estimation and mapping. As this method eliminated the effect of vegetation cover and restored the inherent soil spectra, it not only quantitatively estimates and maps SM at regional scales with high accuracy, but also provides a new way of improving the accuracy of soil organic matter estimation and mapping. 展开更多
关键词 SOIL moisture remote sensing BARE SOIL ALBEDO TRAPEZOID feature space QINGHAI Lake Basin
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Numerical Analysis on Thermal Function of Clothing with PCM Microcapsules 预览
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作者 LIU Wenyi LI Fengzhi LIU Weihua 《南京航空航天大学学报:英文版》 EI CSCD 2019年第2期320-329,共10页
To study the influences of phase change material(PCM)microcapsules in clothing on human thermal responses,a mathematical model is developed.The improved Stolwijk’s model is used to simulate human thermo-regulatory pr... To study the influences of phase change material(PCM)microcapsules in clothing on human thermal responses,a mathematical model is developed.The improved Stolwijk’s model is used to simulate human thermo-regulatory process,and the coupled heat and moisture transfer including the moisture sorption/desorption of fibers and effects of phase transition temperature range on the phase change processes of the PCM is considered in clothing model.Meanwhile,the theoretical predictions are validated by experimental data.Then,the interactions between human body thermal responses and the heat and moisture transfer in clothing are discussed by comparing the prediction results with PCMs and without PCMs.Also the effects of fiber hygroscopicity on clothing and human thermal responses are compared.The conclusion shows that the clothing with PCMs microcapsules can delay the human temperature variations and decrease the sweat accumulation rate on the skin surface and heat loss during changing of ambient conditions,and fiber hygroscopicity reduces the effect of PCM microcapsules on delaying garment temperature variations very significantly. 展开更多
关键词 PCM MICROCAPSULE porous textiles heat and MOISTURE transfer numerical simulation human thermoregulatory model
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Uncertainty on Design Critical Rainfall for Flash Flood Early Warning : A Case Study of South Branch Watershed of Censhui 预览
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作者 Li Changzhi Zhang Xiaolei +2 位作者 Zhang Miao Sun Dongya Guo Liang 《气象与环境研究:英文版》 CAS 2019年第1期31-38,42共9页
Critical rainfall estimation for early warning of rainstorm-induced flash flood is an inverse rainstorm-0x09runoff process based on warning discharge threshold for a warning station of interest in a watershed;the key ... Critical rainfall estimation for early warning of rainstorm-induced flash flood is an inverse rainstorm-0x09runoff process based on warning discharge threshold for a warning station of interest in a watershed;the key aspects of critical rainfall include rainfall amount and rainfall duration. Antecedent moisture content and storm pattern affects highly the estimation of critical rainfall. Using hydrological modeling technique with detailed sub-basin delineation and manual for design rainstorm-runoff computation, this study first introduced basic concept and analysis methods on critical rainfall for flash flood early warning, and then investigated the responses of flash flood warning critical rainfall to antecedent moisture content and storm pattern. Taking South Branch Watershed of Censhui in Hunan Province as an example, critical rainfall in scenarios of typical antecedent moisture content and storm patterns was estimated at 3 warning stations of interest in this watershed. This research illustrates that both antecedent and storm pattern play important role in the estimation of critical rainfall and enough attention should also be paid to these factors when a decision to be made on whether a warning to be issued or not. 展开更多
关键词 UNCERTAINTY DESIGN critical RAINFALL ANTECEDENT moisture content STORM pattern
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稀奶油对农家干酪品质的影响 预览
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作者 孙金威 杨晓凤 +2 位作者 李启明 朱雅丽 唐果 《食品与发酵科技》 CAS 2019年第4期122-127,共6页
研究稀奶油对农家干酪品质的影响,确定农家干酪中稀奶油的最适添加量。采用短时发酵工艺的方法,设计5组实验,通过添加不同比例的稀奶油制作农家干酪,国标法分别测定五组实验中农家干酪的水分含量和蛋白质含量,质构仪和流变仪测定产品质... 研究稀奶油对农家干酪品质的影响,确定农家干酪中稀奶油的最适添加量。采用短时发酵工艺的方法,设计5组实验,通过添加不同比例的稀奶油制作农家干酪,国标法分别测定五组实验中农家干酪的水分含量和蛋白质含量,质构仪和流变仪测定产品质构和相应流变学特性,同时对干酪产率和融化特性进行评估,最后从风味,质地及外观上对农家干酪进行感官学品评测试。结果表明:随着稀奶油添加量的增多,干酪的水分含量增加;产率增加;硬度下降;弹性模量降低;干酪风味和外观评分逐渐升高。确定农家干酪中的稀奶油最适添加量为5.2%。 展开更多
关键词 农家干酪 稀奶油 产率 质构
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基于FDS区分热老化和水分对油纸绝缘状态的影响研究 预览
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作者 张可迪 胡康 刘翔 《电工电气》 2019年第5期58-61,共4页
为区分热老化和水分对频域介电特性的影响,将FDS法应用于变压器主绝缘的老化和受潮状态评估。通过绝缘诊断仪对制备的老化和水分试品进行FDS测量,提取1mHz及0.1mHz为老化试品特征频率,100Hz、1kHz为水分试品特征频率,利用特征频率处的ta... 为区分热老化和水分对频域介电特性的影响,将FDS法应用于变压器主绝缘的老化和受潮状态评估。通过绝缘诊断仪对制备的老化和水分试品进行FDS测量,提取1mHz及0.1mHz为老化试品特征频率,100Hz、1kHz为水分试品特征频率,利用特征频率处的tanδ区分老化和水分对频域介电特性的影响,并给出了特征频率处tanδ与聚合度以及水分含量的定量拟合关系。研究结果表明:聚合度和水分含量与特征频率处的tanδ均呈指数函数关系,tanδ随着聚合度增大而减小,随着水分含量的增大而增大。 展开更多
关键词 变压器 油纸绝缘 频域介电谱 热老化 水分 特征频率 介质损耗
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果实生长与果园土壤含水量的变化对'茂谷柑'裂果的影响 预览
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作者 赖呈纯 黄贤贵 +3 位作者 王琦 陈源 高慧颖 谢鸿根 《福建农林大学学报:自然科学版》 CSCD 北大核心 2019年第4期434-439,共6页
以7年生'茂谷柑'果树及其所在的果园土壤为研究对象,测定'茂谷柑'果实的裂果率、纵横径、果皮厚度,并对果园土壤的含水量进行了测定,同时采用适时喷灌的措施防止裂果.结果表明:'茂谷柑'果实紧实,纵横径的快速... 以7年生'茂谷柑'果树及其所在的果园土壤为研究对象,测定'茂谷柑'果实的裂果率、纵横径、果皮厚度,并对果园土壤的含水量进行了测定,同时采用适时喷灌的措施防止裂果.结果表明:'茂谷柑'果实紧实,纵横径的快速增长及果皮的迅速变薄,是裂果发生的重要内在因素;而果园土壤水分的亏缺和不规律变化,是诱发裂果的关键外部因素.无喷灌措施的自然条件下,裂果率可达到18%以上,裂果主要集中在8月中旬至11月下旬.采用适时喷灌的措施,使土壤含水量保持较均衡并在临界值之上,可有效防止裂果,裂果率可以控制在5.0%以下,极大地降低裂果的发生. 展开更多
关键词 '茂谷柑' 柑橘 果实生长 裂果 水分
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提高烧结开机成品率的创新实践 预览
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作者 顾亚楠 《河北冶金》 2019年第7期33-35,共3页
为进一步降低烧结生产成本,解决烧结系统在开机时因水分不稳定、料层不均、点火质量差、漏风等因素造成成品率低下的问题,河钢宣钢在360m^2烧结机系统进行了一系列创新。通过开发自动加水系统、量化加水时间和加水量、优化过程参数、实... 为进一步降低烧结生产成本,解决烧结系统在开机时因水分不稳定、料层不均、点火质量差、漏风等因素造成成品率低下的问题,河钢宣钢在360m^2烧结机系统进行了一系列创新。通过开发自动加水系统、量化加水时间和加水量、优化过程参数、实施标准化操作等措施,开机后产生的落地料由平均88.6t/次减少至22t/次,开机成品率由67.1%提高至80%。 展开更多
关键词 烧结 开机成品率 混合料 水分 自动加水系统
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基于机器视觉的工夫红茶萎凋叶水分检测 预览
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作者 梁高震 胡斌 +2 位作者 董春旺 江用文 罗昕 《石河子大学学报:自然科学版》 CAS 北大核心 2019年第1期79-86,共8页
萎凋是工夫红茶加工的首道工序,萎凋叶水分检测主要依赖于人工经验判断,难以做到精准、客观和量化评价。本文针对萎凋叶摊放工艺,以工夫红茶萎凋在制品为研究对象,基于机器视觉技术获取萎凋叶图像的色泽和纹理特征信息,分析图像特征变... 萎凋是工夫红茶加工的首道工序,萎凋叶水分检测主要依赖于人工经验判断,难以做到精准、客观和量化评价。本文针对萎凋叶摊放工艺,以工夫红茶萎凋在制品为研究对象,基于机器视觉技术获取萎凋叶图像的色泽和纹理特征信息,分析图像特征变量的变化规律及其与水分的关联;采用偏最小二乘法PLS(Partial least squares)、极限学习机ELM(Exterme learning machine)和支持向量机回归SVR(Support vector machine regression)方法,分别建立萎凋叶水分定量预测模型。结果表明:3种预测方法预测值和实际值的相关系数均大于0.95,非线性 SVR模型明显优于PLS模型和ELM模型,其预测集的相关系数Rp(Correlation coefficient of predication set)和预测均方根RMSEP(Root-mean-square error of prediction)分别为0.9904和0.0118,预测集绝对误差均小于0.05,相对标准偏差RPD(Relative percent deviation)值为6.6264。这说明SVR方法能够更好表征图像信息与水分之间的量化解析关系,具有更优的泛化性和鲁棒性,为萎凋加工中水分含量快速无损检测提供了解决方案,为工夫红茶水分在线检测装置的开发提供理论基础,对茶叶机械智能化的发展具有重要意义。 展开更多
关键词 工夫红茶 机器视觉 萎凋 水分 定量预测
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Influences of soil moisture and salt content on loess shear strength in the Xining Basin, northeastern Qinghai-Tibet Plateau
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作者 FU Jiang-tao HU Xia-song +5 位作者 LI Xi-lai YU Dong-mei LIU Ya-bin YANG You-Qing QI Zhao-xin LI Shu-xia 《山地科学学报:英文版》 SCIE CSCD 2019年第5期1184-1197,共14页
Moisture and salt content of soil are the two predominant factors influencing its shear strength. This study aims to investigate the effects of these two factors on shear strength behavior of loess in the Xining Basin... Moisture and salt content of soil are the two predominant factors influencing its shear strength. This study aims to investigate the effects of these two factors on shear strength behavior of loess in the Xining Basin of Northeast Qinghai-Tibet Plateau, where such geological hazards as soil erosion, landslides collapse and debris flows are widespread due to the highly erodible loess. Salinized loess soil collected from the test site was desalinized through salt-leaching in the laboratory. The desalinized and oven-dried loess samples were also artificially moisturized and salinized in order to examine how soil salinity affects its shear strength at different moisture levels. Soil samples prepared in different ways(moisturizing, salt-leaching, and salinized) were measured to determine soil cohesion and internal friction angle. The results show that salt-leaching up to 18 rounds almost completely removed the salt content and considerably changed the physical components of loess, but the soil type remained unchanged. As salt content increases from 0.00% to 12.00%, both the cohesion and internal friction angle exhibit an initial decrease and then increase with salt content. As moisture content is 12.00%, the salt content threshold value for both cohesion and internal friction angle is identified as 3.00%. As the moisture content rises to 16.0% and 20.00%, the salt content threshold value for cohesion is still 6.00%, but 3.00% for internal friction angle. At these thresholds soil shear strength is the lowest, below which it is inversely related to soil salinity. Beyond the thresholds, however, the relationship is positive. Dissimilar to salinity, soil moisture content exerts an adverse effect on shear strength of loess. The findings of this study can provide a valuable guidance on stabilizing the engineering properties of salinized loess to prevent slope failures during heavy rainfall events. 展开更多
关键词 Salinized LOESS Desalinized LOESS Salt-leaching Shear strength indices Moisture CONTENT Salt CONTENT
温度和水分对典型香型烟区植烟土壤氮素矿化的影响
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作者 高真真 段卫东 +4 位作者 胡坤 王俊 杨惠娟 李洪亮 史宏志 《土壤》 CAS CSCD 北大核心 2019年第3期442-450,共9页
为探究典型香型烟区植烟土壤氮素矿化特征及其与温度和水分的关系,采用室内培养试验研究了土壤温度(15、28、37℃)和土壤相对含水量(50%、65%、80% 田间持水量)对云南大理、贵州毕节、河南许昌3个典型香型产区植烟土壤氮素矿化的影响.... 为探究典型香型烟区植烟土壤氮素矿化特征及其与温度和水分的关系,采用室内培养试验研究了土壤温度(15、28、37℃)和土壤相对含水量(50%、65%、80% 田间持水量)对云南大理、贵州毕节、河南许昌3个典型香型产区植烟土壤氮素矿化的影响.结果表明:不同地区植烟土壤矿质氮和矿化速率变化规律与温度和水分密切相关.3个产区植烟土壤的矿质氮含量和矿化速率均随着温度的升高而升高,在同一温度条件下,以土壤有机质含量较高的云南大理土壤矿化量较大,有机质含量较低的河南许昌土壤矿化量较小.不同地区植烟土壤含水量与氮素矿化的关系不尽相同,土壤相对黏重的贵州毕节土壤以50% 田间持水量处理土壤氮素矿化量和矿化速率最大,以80% 田间持水量处理最不利于氮素矿化;而质地相对较轻的河南许昌土壤和云南大理土壤均为在65% 田间持水量条件下最有利于氮素矿化,以50% 田间持水量处理氮素矿化量较小.基于一级动力学方程的模拟,3个植烟土壤的潜在矿化氮库(N0)都随温度的增加而提高,总体以28~37℃的培养温度较为适宜,低于15℃不利于土壤有机氮的矿化,3个植烟土壤的N0以云南大理最高,河南许昌最低;土壤矿化速率常数(K)以云南大理最大.土壤相对含水量也对N0有一定影响,且土壤温度和含水量对不同土壤氮素矿化量和矿化速率均存在显著的互作影响,合理调控土壤温度和土壤相对含水量,可以有效调节不同生态烟区土壤氮素矿化动态变化. 展开更多
关键词 烟草 土壤 氮素矿化 矿化速率 温度 水分
An efficient analytical homogenization technique for mechanical-hygrothermal responses of unidirectional composites with applications to optimization and multiscale analyses
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作者 Guannan WANG 《中国航空学报:英文版》 SCIE EI CAS CSCD 2019年第2期382-395,共14页
The elasticity-based Locally Exact Homogenization Theory(LEHT) is extended to study the mechanical-hygrothermal behaviors of unidirectionally-reinforced composites. Based on the framework developed previously, thermal... The elasticity-based Locally Exact Homogenization Theory(LEHT) is extended to study the mechanical-hygrothermal behaviors of unidirectionally-reinforced composites. Based on the framework developed previously, thermal and moisture effects are incorporated into the LEHT to study the homogenized and localized responses of heterogeneous materials, which are validated using available analytical and numerical techniques. The LEHT programs are then encapsulated as subroutines with Input/Output(I/O) interfaces, to be readily applied in different computational scenarios. In order to illustrate the efficiency of the LEHT, the theory is firstly coupled to the Particle Swarm Optimization(PSO) algorithm in order to minimize the axial thermal expansion mismatch in hexagonal and square fiber arrays by tailoring the fiber volume fraction. The LEHT is then implemented into the lamination theory to study fabrication-induced residual stresses arising during the cool-down process which introduces local laminate stresses owing to thermo-mechanical property mismatch between plies. Both of these applications illustrate the efficiency and accuracy of the LEHT in generating effective properties and local stress distributions, making the theory a golden standard in validating other analytical or numerical techniques as well as a reliable tool in composite design and practice for professionals and non-professionals alike. 展开更多
关键词 COEFFICIENTS of moisture EXPANSION COEFFICIENTS of thermal EXPANSION Elasticity-based LOCALLY exact HOMOGENIZATION theory Mechanical-hygrothermal behavior Multiscale laminate analysis Particle swarm OPTIMIZATION
ZCCA压滤机在纳林河二号选煤厂的应用
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作者 王海波 《煤炭技术》 CAS 2019年第1期149-151,共3页
简述了中煤(天津)洗选科技有限公司生产的ZCCA压滤机的工作流程、技术特点及在纳林河二号选煤厂煤泥脱水方面的情况;并与现场原有压滤机、加压过滤机实际使用情况进行了比较。结果表明:此压滤机具有产品水分低、处理量大的优点,它降低... 简述了中煤(天津)洗选科技有限公司生产的ZCCA压滤机的工作流程、技术特点及在纳林河二号选煤厂煤泥脱水方面的情况;并与现场原有压滤机、加压过滤机实际使用情况进行了比较。结果表明:此压滤机具有产品水分低、处理量大的优点,它降低了混煤(-6 mm原煤及煤泥)水分,缓解了溜槽堵塞问题,节省了人工成本,减少了设备投资,提高了产品品质。 展开更多
关键词 压滤机 选煤厂 水分 应用
芊玖舒胶囊的吸湿稳定性研究
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作者 吴琼 梁茜 +2 位作者 江帆 骆衡 安崇惠 《华西药学杂志》 CAS CSCD 2019年第2期203-206,共4页
目的为提高芊玖舒胶囊在大生产中的吸湿稳定性,优化浸膏干燥技术及颗粒制备参数。方法采用浸膏预混辅料新技术,以95%乙醇作为润湿剂制粒,以水分、葛根素、总黄酮、灰分、崩解时限、性状等为主要考察指标,考察产品的影响因素、加速稳定... 目的为提高芊玖舒胶囊在大生产中的吸湿稳定性,优化浸膏干燥技术及颗粒制备参数。方法采用浸膏预混辅料新技术,以95%乙醇作为润湿剂制粒,以水分、葛根素、总黄酮、灰分、崩解时限、性状等为主要考察指标,考察产品的影响因素、加速稳定性及长期稳定性。结果颗粒剂流动性改善良好,休止角达到33.3度,相对临界湿度为80.2%,高湿环境是影响稳定性的重要因素;3批产品加速、长期稳定性符合规定。结论大生产工艺中采用浸膏预混淀粉干燥分散新技术及95%乙醇制粒工艺能有效提高产品吸湿的稳定性,可为药物制剂工艺在保健食品大生产中的应用提供参考。 展开更多
关键词 芊玖舒胶囊 制粒方法 吸湿性 稳定性 葛根素 总黄酮 水分 灰分
含气页岩中水分赋存与分布的研究进展 预览
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作者 罗翠娟 张登峰 +4 位作者 赵春鹏 伦增珉 王海涛 李艳红 杨劲 《化工进展》 EI CAS CSCD 北大核心 2019年第6期2726-2737,共12页
页岩气(主要组分为甲烷,CH4)作为一种新兴的非常规天然气,对于优化我国现行能源消费结构、缓解能源消耗过程中的环境污染问题具有重要意义。研究表明,含气页岩储层中页岩气主要以吸附态形式存在。影响含气页岩吸附性能的因素包括页岩自... 页岩气(主要组分为甲烷,CH4)作为一种新兴的非常规天然气,对于优化我国现行能源消费结构、缓解能源消耗过程中的环境污染问题具有重要意义。研究表明,含气页岩储层中页岩气主要以吸附态形式存在。影响含气页岩吸附性能的因素包括页岩自身理化性质和外部储层条件。其中,页岩中的水分是影响页岩气吸附/解吸的重要因素。因此,本文结合国内外相关研究工作,分析了含气页岩中水分的赋存与分布特征,归纳了页岩储层中水分的分析方法,指出了水分赋存与分布的后续研究方向。分析表明:①页岩中水分主要赋存于孔隙结构中,且无机孔隙中的水分赋存量比有机孔隙多;②水分子主要通过氢键吸附于有机孔隙的亲水性位点,以及经由氢键和表面作用力结合于黏土颗粒或孔隙表面;③水分含量与页岩黏土矿物含量及总有机碳(TOC)含量有关;④探明页岩中水分赋存与分布的实验表征手段包括水蒸气等温吸附、低温差示扫描量热、低场核磁共振、红外热成像和等离子体低温灰化等。虽然页岩中水分的研究已经引起国内外学者的关注,但是相比煤中水分的研究仍显不足。因此,本文指出后续需开展以下工作:探明水分在页岩中的无机矿物质空间和有机质空间的含量分布和空间分布特征;明确水分对页岩吸附/解吸CH4流体的作用规律;联用实验科学和理论模拟方法,探明水分对页岩吸附/解吸CH4流体的作用机理。 展开更多
关键词 含气页岩 赋存 页岩气 吸附(作用)/解吸
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Effect of molasses binder on the physical and mechanical properties of iron ore pellets 预览
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作者 Anand Babu Kotta Anshuman Patra +1 位作者 Mithilesh Kumar Swapan Kumar Karak 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2019年第1期41-51,共11页
Molasses was used as an alternative binder to the bentonite binder.The change in moisture absorption by pellets prepared with different iron ores and different molasses contents were investigated.Iron ore properties e... Molasses was used as an alternative binder to the bentonite binder.The change in moisture absorption by pellets prepared with different iron ores and different molasses contents were investigated.Iron ore properties exerted the major effect on pellet behavior and final pellet quality.The absorbed moisture content of pellets prepared without binder,bentonite-added pellets,and molasses-added pellets were in the range of 7.72%–9.95%,9.62%–10.84%,and 6.14%-6.69%,respectively.The wet pellet compressive strength of molasses-added pellets(43–230 N/pellet)was superior to that of bentonite-added pellets(9.47–11.92 N/pellet).The compressive strength of dried molasses-modified pellets increased to 222–394 N/pellet,which is currently the highest value achieved for dried pellets. 展开更多
关键词 iron ORE MOLASSES BINDER MOISTURE ABSORPTION PELLET strength physical and mechanical properties
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费休氏容量滴定法测定注射用重组人干扰素α2a中水含量的测量不确定度评定 预览
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作者 冯雪 李野 +5 位作者 刘沛衡 耿雪莹 赵丽佳 刘华 柳春红 杨红育 《生物化工》 2019年第2期73-76,共4页
目的:对费休氏容量滴定法测定注射用重组人干扰素α2a中水含量实验方法进行不确定度评定。方法:分析测定过程中引入的不确定度分量的主要来源,对不确定度分量进行了计算评定。结果:测定结果不确定度的主要来源是标定滴定度及样品重复测... 目的:对费休氏容量滴定法测定注射用重组人干扰素α2a中水含量实验方法进行不确定度评定。方法:分析测定过程中引入的不确定度分量的主要来源,对不确定度分量进行了计算评定。结果:测定结果不确定度的主要来源是标定滴定度及样品重复测定引入的不确定度。结论:正确评估测定过程中的不确定度是提高水分测定准确度的关键。可通过选用灵敏度高的天平降低不确定度。 展开更多
关键词 水分 重组人干扰素Α2A 费休氏容量滴定法 不确定度
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Assessing the Performance of Separate Bias Kalman Filter in Correcting the Model Bias for Estimation of Soil Moisture Profiles
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作者 Bangjun CAO Fuping MAO +2 位作者 Shuwen ZHANG Shaoying LI Tian WANG 《气象学报:英文版》 SCIE CSCD 2019年第3期519-527,共9页
The performance of separate bias Kalman filter (SepKF) in correcting the model bias for the improvement of soil moisture profiles is evaluated by assimilating the near-surface soil moisture observations into a land su... The performance of separate bias Kalman filter (SepKF) in correcting the model bias for the improvement of soil moisture profiles is evaluated by assimilating the near-surface soil moisture observations into a land surface model (LSM). First, an observing system simulation experiment (OSSE) is carried out, where the true soil moisture is known, two types of model bias (i.e., constant and sinusoidal) are specified, and the bias error covariance matrix is assumed to be proportional to the model forecast error covariance matrix with a ratio λ. Second, a real assimilation experiment is carried out with measurements at a site over Northwest China. In the OSSE, the soil moisture estimation with the SepKF is improved compared with ensemble Kalman filter (EnKF) without the bias filter, because SepKF can properly correct the model bias, especially in the situation with a large model bias. However, the performance of SepKF becomes slightly worse if the constant model bias increases or temporal variability of the sinusoidal model bias becomes large. It is suggested that the ratio λ should be increased (decreased) in order to improve the soil moisture estimation if temporal variability of the sinusoidal model bias becomes high (low). Finally, the assimilation experiment with real observations also shows that SepKF can further improve the estimation of soil moisture profiles compared with EnKF without the bias correction. 展开更多
关键词 soil moisture BIAS correction ENSEMBLE KALMAN filter (EnKF) Noah-MP
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