期刊文献+
共找到94篇文章
< 1 2 5 >
每页显示 20 50 100
纱线在织物的屈曲和织物厚度 被引量:2
1
作者 邢连华 《天津工业大学学报》 CAS 北大核心 1990年第Z1期109-115,共7页
本文用数学解析法研究了机织物中经、纬纱的屈曲状态和织物厚度的关系,特别提出了纱线屈曲角和屈曲波系数及其在处理上述关系中的重要作用。从理论上阐述了织物结构相诸参数间的解析关系。对由不同特数经、纬纱、所形成的同支持面的结构... 本文用数学解析法研究了机织物中经、纬纱的屈曲状态和织物厚度的关系,特别提出了纱线屈曲角和屈曲波系数及其在处理上述关系中的重要作用。从理论上阐述了织物结构相诸参数间的解析关系。对由不同特数经、纬纱、所形成的同支持面的结构相,提出新的命名建议。 展开更多
关键词 结构相 纱线屈曲角 屈曲波系数 支持面
下载PDF
核电稳压器安全阀动作性能仿真及数学模型建立 被引量:8
2
作者 王媛媛 王亮 +3 位作者 田野 张健 于新海 商华政 《流体机械》 CSCD 北大核心 2022年第2期89-96,共8页
为了实现稳压器安全阀的动态模拟,精确计算稳压器安全阀阀瓣的运动状态,采用动网格、流域分块、外接虚拟大容器等模拟技术,并利用二阶微分方程对阀瓣的动态特性进行了编译,使得稳压器安全阀在32 ms实现全开启,在此基础上,基于响应面法... 为了实现稳压器安全阀的动态模拟,精确计算稳压器安全阀阀瓣的运动状态,采用动网格、流域分块、外接虚拟大容器等模拟技术,并利用二阶微分方程对阀瓣的动态特性进行了编译,使得稳压器安全阀在32 ms实现全开启,在此基础上,基于响应面法对影响稳压器安全阀启闭压差的因素进行了分析,拟合了回座压力的计算公式,最后检验模拟值与实验值误差是否小于5%,验证方法的可行性,本文为稳压器安全阀的设计和现场调试提供了精确的数学模型。 展开更多
关键词 弹簧式稳压阀 流动性能 弹簧刚度 调节圈位置 响应面法
下载PDF
我国未来可利用水资源量的估测 被引量:17
3
作者 冯尚友 傅春 《武汉水利电力大学学报》 EI CAS CSCD 1999年第6期6-9,共4页
遵循水资源可持续利用要求,探讨了我国未来可利用的水资源数量问题.其中包括问题的提出、获取可能利用水量的客观困难、考虑的主要因素和估算方法与结果评述.
关键词 水资源 可持续利用 可利用水量 估测
原文传递
矿产资源开发与可持续发展 被引量:17
4
作者 朱维根 《中国矿业》 北大核心 2004年第9期44-46,共3页
本文对矿产资源开发引发的资源和环境问题进行了论述 ,提出了一些提高资源回收率、防治矿山塌陷、减少固体废弃物排放的方法。
关键词 可持续发展 矿山塌陷 尾矿 溶浸
下载PDF
缓释技术用于物体表面消毒的初步研究 被引量:3
5
作者 陈妍妍 张宝莹 +3 位作者 王佳奇 沈瑾 王式鸿 张流波 《中国消毒学杂志》 CAS 2023年第4期241-245,共5页
目的石研究缓释型固体二氧化氯以气体释放方式对密闭空间物体表面消毒效果。方法采用载体定量杀菌试验方法,对不同条件下缓释型固体二氧化氯对细菌繁殖体杀灭效果进行观察。结果缓释型固体二氧化氯有效含量和数量、加人试剂种类及加入... 目的石研究缓释型固体二氧化氯以气体释放方式对密闭空间物体表面消毒效果。方法采用载体定量杀菌试验方法,对不同条件下缓释型固体二氧化氯对细菌繁殖体杀灭效果进行观察。结果缓释型固体二氧化氯有效含量和数量、加人试剂种类及加入量、试验菌种、染菌载体类型、消毒剂与染菌载体距离均为缓释型固体二氧化氯对密闭空间物体表面消毒的重要影响因素。在室温10~15℃,相对湿度为20%~30%条件下,30片9.35mg/片缓释型固体二氧化氯加人7.5mL水,消毒作用4h,消毒剂与染菌载体距离为60cm时,通过调整消毒剂放置方式,可实现固体二氧化氯对密闭空间物体表面的消毒。结论缓释型固体二氧化氯加水活化后,在一定空间范围内对常见物体表面有较好的杀菌效果。 展开更多
关键词 二氧化氯 缓释 消毒效果 物体表面
原文传递
Updates on the treatment and outcomes of dual chronic hepatitis C and B virus infection 被引量:3
6
作者 Chun-Jen Liu Pei-Jer Chen 《World Journal of Gastroenterology》 SCIE CAS 2014年第11期2955-2961,共7页
Dual hepatitis C virus(HCV)/hepatitis B virus(HBV)infection is found in HBV or HCV endemic areas,and in specific populations exhibiting a high risk of parenteral viral transmission.Clinical observations have revealed ... Dual hepatitis C virus(HCV)/hepatitis B virus(HBV)infection is found in HBV or HCV endemic areas,and in specific populations exhibiting a high risk of parenteral viral transmission.Clinical observations have revealed that HCV/HBV dually infected patients demonstrate a higher risk of liver disease progression compared with HBV or HCV monoinfected patients.The viral activity responsible for liver disease progression can be determined by examining the viral loads of HCV and HBV and by conducting liver biopsy examinations.Recent trials have confirmed that the combination therapy of peginterferon alpha-2a or 2b and ribavirin for dual hepatitis patients with HCV dominance appears to be as effective and safe as it is in patients with HCV monoinfections.Strikingly,approximately 60% of dually infected patients with inactive hepatitis B before treatment develop HBV reactivation after the clearance of the HCV.The clinical significance of this HBV reactivation and the strategy to prevent and treat this event should be determined.Furthermore,approximately 30%of dually infected patients lost hepatitis B surface antigen(HBsAg)within 5 years after the start of peginterferonbased therapy,and 40%of them harbored occult HBV infection.The underlying mechanisms of their accelerating HBsAg seroclearance and the development of occult HBV await further investigations.Moreover,the optimal treatment strategies for dually infected patients who are seropositive for the hepatitis B e antigen must be explored.Finally,the advent of new direct-acting antiviral-based anti-HCV therapy may change the optimal therapies for patients with dual hepatitis in the near future,which warrants further clinical trials. 展开更多
关键词 Dual infection Hepatitis B virus Hepatitis C virus INTERFERON Pegylated interferon RIBAVIRIN sustained virological response Hepatitis B surface antigen clearance
下载PDF
Application of D-Optimal Study Design with Contour Surface Response for Designing Sustained Release Gliclazide Matrix Tablets 被引量:1
7
作者 Chien Nguyen John Mark Christensen Thuy Nguyen 《Pharmacology & Pharmacy》 2014年第7期620-635,共16页
An optimized formulation of a sustained release tablet of Gliclazide was developed. The use of Doptimal design with a polynomial statistical model to analyze dissolution data reduced the number of laboratory tests req... An optimized formulation of a sustained release tablet of Gliclazide was developed. The use of Doptimal design with a polynomial statistical model to analyze dissolution data reduced the number of laboratory tests required to obtain an optimal dosage form. The final formulation contained 22 mg of Methocel&regE15LV, 16.5 mg Methocel&regE15 and 10.0 mg of Dibasic Calcium Phosphate per 30 mg Gliclazide sustained release tablet. Dissolution studies performed on tablets from 5000 tablet test batches released greater than 90 percent of loaded drug in eight hours. Drug release from the optimized tablets followed a pattern more closely similar to zero-order than other mechanisms of drug release tested. Storage of tablets in accelerated and ambient conditions for 6 and 12 months respectively did not alter any of the physico-chemical properties, drug release or the drug release rate compared to initial observations and dissolution data of the prepared tablets. The addition of potassium phosphate and monosodium phosphate to the tablet reduced the effect pH has on Gliclazide dissolution compared to the commercially available product. 展开更多
关键词 GLICLAZIDE sustainED RELEASE D-Optimal Zero-Order RESPONSE surface Modified RELEASE
下载PDF
PLGA作为抗原递送系统的研究进展 被引量:1
8
作者 郑蕊 屠叶清 +1 位作者 王慧 罗德炎 《中国生物工程杂志》 CAS CSCD 北大核心 2023年第5期69-75,共7页
近年来新冠病毒肆虐,单针剂的疫苗研制备受关注。传统疫苗制剂需要在一段时间内多次反复接种才能产生足够的中和抗体。为了降低疫苗接种次数、提高人们的疫苗接种依从性,高分子聚合物材料逐渐走进人们视野,其中聚乳酸-羟基乙酸共聚物(po... 近年来新冠病毒肆虐,单针剂的疫苗研制备受关注。传统疫苗制剂需要在一段时间内多次反复接种才能产生足够的中和抗体。为了降低疫苗接种次数、提高人们的疫苗接种依从性,高分子聚合物材料逐渐走进人们视野,其中聚乳酸-羟基乙酸共聚物(poly lactic-co-glycolic acid,PLGA)是当前研究最多、应用最广泛的高分子聚合物材料。PLGA作为一种人工合成的高分子聚合物材料,易于制备、价格相对较低,且具有良好的缓释特性,以及生物安全性和组织相容性,已经被FDA批准应用于药物递送系统,但在疫苗研发上方兴未艾。总结了PLGA佐剂的基本信息,根据当前疫苗研究趋势分析整理了影响其缓释效果和免疫调节作用的相关因素,以及当前的不足和限制,为后续疫苗制备和研究提供一些思路。 展开更多
关键词 PLGA 缓释 免疫调节 表面性质
原文传递
Blue emitting CsPbBr3 perovskite quantum dot inks obtained from sustained release tablets 被引量:2
9
作者 Hewei Yang Yaqing Feng +7 位作者 Zhiyu Tu Kuo Su Xiaozhi Fan Bingjie Liu Zhiping Shi Yuzhe Zhang Chenyang Zhao Bao Zhan 《Nano Research》 SCIE EI CAS CSCD 2019年第12期3129-3134,共6页
Blue emitting perovskite ink obtained from cesium lead halide quantum dots bearing chlorine(CsPbClxBr3-x,0<x<3)suffers from the low photoluminescence quantum yield and poor stability.Cesium lead bromine(CsPbBr3)... Blue emitting perovskite ink obtained from cesium lead halide quantum dots bearing chlorine(CsPbClxBr3-x,0<x<3)suffers from the low photoluminescence quantum yield and poor stability.Cesium lead bromine(CsPbBr3)quantum dots free of chlori ne have more stable crystalstructure and fewer crystal defects.Precise control of crystal sizes and surface passivation comporients of CsPbBr3 quantum dots is crucial for the best use of quantum confinement effect and blueshift of emission wavelength to blue region.Here,by polymerizing acrylamide under UV-light irradiation to form polymer gel networks in dimethyl sulfoxide(DMSO)with CsPbBr3 precursors and passivating agents trapped,wesuccessfully prepared novel sustained release tablets with different shapes and sizes.Thanks to the limitation of the polymer networks onsolve nt releasi ng,the resulting CsPbBr3 qua ntum dots have the average size of 1.1±0.2 nm.On the basis of the excelle nt quantum confin eme nteffect and optimized surface passivation,the obtained PQD ink can emit high quality blue light for more than 6 weeks.This work elucidates anew and convenient technique to prepare blue emission perovskite quantum dots ink with high stability and photoluminescence qua ntumyield and provides a great potential technology for the preparation of perovskite optoelectronic devices. 展开更多
关键词 sustained release TABLET PEROVSKITE quantum dot BLUE EMITTING PEROVSKITE ink polymer gel surface passivation
原文传递
A Geospatial Approach to Measuring Surface Disturbance Related to Oil and Gas Activities in West Florida, USA
10
作者 Chris W. Baynard Robert W. Schupp +1 位作者 Pingying Zhang Paul Fadil 《Advances in Remote Sensing》 2014年第2期77-93,共17页
Oil and gas exploration and production activities (OGEPA) can produce surface disturbances created by the construction of roads, well pads, oil wells, pipelines, production facilities and storage pits. These alteratio... Oil and gas exploration and production activities (OGEPA) can produce surface disturbances created by the construction of roads, well pads, oil wells, pipelines, production facilities and storage pits. These alterations can range from landscape conversion to transformation depending on location, regulations and enforcement, environmental best practices and state vs. multinational management. Though not known as a major oil and gas state, Florida is ranked 23rd in gas and 24th in oil production nationally. Jay oilfield, located in West Florida’s panhandle region, is the largest and top producer in the state. Though production peaked in 1979, a nationwide upsurge is taking place that could affect Florida. The accounting from above approach proposed here is well suited to understand the role that the infrastructure surface footprint has on West Florida’s landscape and how to monitor potential changes underway. It involves remote sensing, GIS techniques and landscape ecology metrics to quantify surface disturbance in Santa Rosa County’s six oilfields and then ranks each field based on environmental performance (sustainability). Findings suggest that agricultural conversion is the leading driver of land-use and land-cover (LULC) change, while OGEPA have created small-scale surface alterations. This paper’s approach can help oil companies, land managers and local government authorities understand the spatial extent of OGEPA onshore alterations and plan future scenarios, particularly as drilling and production increase in the current shale revolution occurring throughout the US, as well as expanded drilling planned for Florida. 展开更多
关键词 Oil and Gas Landscape DISTURBANCE Environmental Management GEOSPATIAL Technologies Infrastructure FOOTPRINT ACCOUNTING surface FOOTPRINT Geo-sustainability
下载PDF
Multiscale Characterization of Automotive Surface Coating Formation for Sustainable Manufacturing 被引量:1
11
作者 Jie XIAO Jia LI Cristina Piluso Yinlun HUANG 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第3期416-423,共8页
Automotive surface coating manufacturing is one of the most sophisticated and expensive steps in automotive assembly. This step involves generating multiple thin layers of polymeric coatings on the vehicle surface thr... Automotive surface coating manufacturing is one of the most sophisticated and expensive steps in automotive assembly. This step involves generating multiple thin layers of polymeric coatings on the vehicle surface through paint spray and curing in a multistage, dynamically changing environment. Traditionally, the quality control is solely post-process inspection based, and process operational adjustment is only experience based, thus the manufacturing may not be (highly) sustainable. In this article, a multiscale system modeling and analysis methodology is introduced for achieving a sustainable application of polymeric materials through paint spray and film curing in automotive surface coating manufacturing. By this methodology, the correlations among paint material, application processes and coating performance can be identified. The model-based analysis allows a comprehensive and deep study of the dynamic behaviors of the material, process, and product in a wide spectrum of length and time. Case studies illustrate the efficacy of the methodology for sustainable manufacturing. 展开更多
关键词 sustainable manufacturing multiscale modeling and analysis automotive surface coating
下载PDF
RELATIVITY AND SUSTAINABLE DEVELOPMENT 被引量:1
12
作者 YEDai-fu 《Chinese Geographical Science》 SCIE CSCD 2004年第1期75-81,共7页
From the realism of science, and taking the guide of EINSTEIN’s Relativity as guide, this article called in question the present theory of the sustainable development by the rational thinking of philosophy and a clos... From the realism of science, and taking the guide of EINSTEIN’s Relativity as guide, this article called in question the present theory of the sustainable development by the rational thinking of philosophy and a close logic inference. It is found that there are many paradoxes to the theory. Through more deepening and meticulous inference, we arrived at philosophic language of science about the sustainable development. The sustainable development is "non-sustainable development", and the non-sustainable development is "the best sustainable development". While carrying out philosophical principle thinking and repeating science demonstration for the sustainable development, this article got further confirmation that the existence of human being at the minimum environment cost may help them obtain motive power of the sustainable development. In fact, this foundation motive power exists in the flow of development in different organization levels, meanwhile it exists in strategy of intuition living of the ancient people. Only in relative lower environment cost to live can we get the support system of science for the sustainable development, and be able really to achieve the basic goal of the sustainable development. 展开更多
关键词 the Relativity sustainable development existence at minimum environment cost relative development surface
下载PDF
Alternative feedstock for the production of activated carbon with ZnCl_(2):Forestry residue biomass and waste wood
13
作者 Dominik Bosch Jan OBack +3 位作者 David Gurtner Sara Giberti Angela Hofmann Anke Bockreis 《Carbon Resources Conversion》 2022年第4期299-309,共11页
In order to substitute fossil resources in activated carbon(AC)production,recent efforts have focused on the utilization of renewable raw materials.Regions with important wood industries offer two potentially underest... In order to substitute fossil resources in activated carbon(AC)production,recent efforts have focused on the utilization of renewable raw materials.Regions with important wood industries offer two potentially underestimated resource types:forestry residue biomass(FRB)and waste wood(WW).Although these materials are widely available(approx.130 mio.m3a-1 FRB,approx.50 mio.ta^(-1) WW in the EU),they are mostly valorised through energy production,as they are high in ashes and may be contaminated with organics and heavy metals.In this study,both FRB and WW were treated via one-step pyrolysis for AC production.ZnCl_(2) was applied as activating agent at pyrolysis temperatures varying from 400 to 600℃ and residence times between 1 and 3 h.Overall,76 samples were prepared and characterized thoroughly via elemental analysis,N_(2)/CO_(2) ad/-desorption,thermogravimetric analysis(TGA),scanning electron microscopy(SEM),and infrared spectroscopy(FTIR).The produced carbons showed specific surface areas of up to 1430 m2g􀀀1 and a pore size distribution with a micropore share of up to 80%.The presence of oxygen-containing functional groups was confirmed via FTIR.Potential feedstock contamination can be mitigated,as minerals and heavy metals could be leached out(up to-99.15%)by an additional wash step and organic contamination undergoes thermal cracking during pyrolysis.The presented study could be a next step in upcycling considerable waste streams from the wood sector through localised and non-fossil-based AC production. 展开更多
关键词 sustainable resources Waste wood Forestry residue Activated carbon Chemical activation PYROLYSIS Porosity Functionalized surface
原文传递
“人类中心主义”在可持续发展中的诠释
14
作者 周晓桂 《安徽工业大学学报(社会科学版)》 2001年第3期43-44,49,共3页
可持续发展是一种新的“人类中心主义”的发展观,它不仅要使生态危机达到生态和谐,而且要使世态危机、人态危机达到世态和谐、人态和谐。
关键词 人类中心主义 可持续发展 显层面 深层面
下载PDF
THERMAL PERFORMANCE OF FELT TYPE VEGETATED FACADE SYSTEMS IN A TEMPERATE CLIMATE DURING HEATING AND COOLING PERIODS
15
作者 Elif Özer Yüksel Nil Türkeri 《Journal of Green Building》 2021年第4期199-225,共27页
Using vegetated facade systems(VFS)as a sustainable solution for existing and new buildings and evaluating thermal performance of these sytems are not a new concept.However,there is a gap in literature about measuring... Using vegetated facade systems(VFS)as a sustainable solution for existing and new buildings and evaluating thermal performance of these sytems are not a new concept.However,there is a gap in literature about measuring thermal performance of VFS applied on an insulated wall.Also,in the research literature,there are few studies measuring thermal performance of felt type VFS in temperate climates,and data about the thermal performance of VFS during winter periods is still scarce.Thus,the aim of the present study is to measure the thermal performance of a felt type VFS applied on a thermal insulated existing wall that us located in Kocaeli,Turkey,under Csa climate conditions during heating and cooling periods.Test results indicate that the felt type VFS acts as a shading device and has a positive contribution to the thermal performance of building walls during a cooling period.In daytime when there is a high amount of solar radiation,felt type VFS decreased exterior surface temperatures of the insulated existing wall by a maximum of 24.4℃,32.2℃ and 37.2℃,in spring,summer and fall periods,respectively.Additionally,indoor air temperatures of the vegetated facade were lower than indoor air temperatures of the reference facade with the maximum difference of 1.8℃ during the cooling period.Also,test results indicate that the vegetated facade never dropped to below 0℃ while exterior surface temperatures of the reference facade dropped below 0℃ at nighttime in the winter period.Thus,it can be claimed that the felt type VFS behaves as a thermal buffer and enhances the thermal performance of the exterior wall of the existing building during heating periods at nighttime.As a conclusion,although differences between exterior surface temperatures of vegetated and reference walls were high,differences between interior surface temperatures of vegetated and reference walls were not meaningful.That is due to the fact that the existing building exterior wall assembly includes 5 cm thickness thermal insulation material which 展开更多
关键词 living walls felt type vegetation facade systems sustainability field measurements thermal performance surface temperature
下载PDF
自由支撑银薄膜的形貌演化规律及机理研究
16
作者 洪阳 陈苗根 +1 位作者 周红 余森江 《台州学院学报》 2010年第3期34-41,共8页
采用直流磁控溅射方法在硅油基底上沉积出具有自由支撑边界条件的金属银薄膜系统,研究了银薄膜在大气环境中的表面形貌演化规律及其物理机理。实验发现银薄膜在真空状态下基本稳定,但在大气环境中发生强烈的收缩效应,使得薄膜开裂,其表... 采用直流磁控溅射方法在硅油基底上沉积出具有自由支撑边界条件的金属银薄膜系统,研究了银薄膜在大气环境中的表面形貌演化规律及其物理机理。实验发现银薄膜在真空状态下基本稳定,但在大气环境中发生强烈的收缩效应,使得薄膜开裂,其表面覆盖率不断降低。分析表明这一动态演化过程基本满足指数衰减规律,并可用薄膜内应力的不断释放加以解释。随着银薄膜的不断收缩,薄膜表面可呈现出异常丰富的褶皱形貌:在薄膜边界附近呈现基本垂直于边界的直线状条纹结构;而在薄膜中间区域,将形成二次起皱的扭曲状花样和无序网格状褶皱形貌。从单轴应力和双轴应力理论的角度出发,对各类奇特的褶皱形貌进行了细致的分析和讨论。 展开更多
关键词 银薄膜 自由支撑 表面形貌 内应力 褶皱
下载PDF
星点设计-效应面法在酒石酸美托洛尔缓释微丸处方优化中的应用 被引量:20
17
作者 黄健 高春生 +1 位作者 单利 梅兴国 《中国药学杂志》 CAS CSCD 北大核心 2007年第7期512-515,共4页
目的本研究以Eudragit RS30D和Eudragit RL30D的混合物为包衣材料,制备日服2次的酒石酸美托洛尔包衣缓释微丸,并将星点设计-效应面法应用于处方筛选过程中。方法以微丸在1,4,8h的释放度作为考察指标,将Eudragit RS30D与Eudragit RL30D... 目的本研究以Eudragit RS30D和Eudragit RL30D的混合物为包衣材料,制备日服2次的酒石酸美托洛尔包衣缓释微丸,并将星点设计-效应面法应用于处方筛选过程中。方法以微丸在1,4,8h的释放度作为考察指标,将Eudragit RS30D与Eudragit RL30D的比例和包衣增重为自变量,采用星点设计-效应面优化法,对缓释包衣处方进行优化。结果经F2(相似因子)检验,3批自制样品的释药曲线与理论释药曲线基本一致。结论星点设计-效应面优化法可用于酒石酸美托洛尔微丸缓释包衣处方的优化,所建模型具有较好的预测能力和实用性。 展开更多
关键词 酒石酸美托洛尔 优特奇RS 30D /L特奇RL 30D 包衣缓释微丸 星点设计-效应面法
下载PDF
采煤塌陷区生态地质环境恢复治理与可持续发展问题的探讨 被引量:15
18
作者 司双印 张运备 +2 位作者 马敬杰 贺留兰 秦世昌 《地质灾害与环境保护》 2004年第3期11-16,共6页
 扼要介绍了济宁市煤炭开发的资源状况和环境问题,提出了3种塌陷区土地复垦方法,并探讨了集发展农业资源、美化生活环境、实现经济效益为一体的塌陷区总体治理方案。通过项目投资分析,确认塌陷区治理能够成为以实现利润为目的的产业化...  扼要介绍了济宁市煤炭开发的资源状况和环境问题,提出了3种塌陷区土地复垦方法,并探讨了集发展农业资源、美化生活环境、实现经济效益为一体的塌陷区总体治理方案。通过项目投资分析,确认塌陷区治理能够成为以实现利润为目的的产业化项目。 展开更多
关键词 生态地质 环境保护 可持续发展 采煤塌陷区 土地复垦
下载PDF
Surface runoff processes and sustainable utilization of water resources in Manas River Basin, Xinjiang, China 被引量:18
19
作者 HongBo LING HaiLiang XU +1 位作者 JinYi FU XinHua LIU 《Journal of Arid Land》 SCIE 2012年第3期271-280,共10页
Water is the important resource to guarantee the existence and development of oases in arid areas. To improve the utilization efficiency of water resources in Manas River Basin, this paper investigated the trends and ... Water is the important resource to guarantee the existence and development of oases in arid areas. To improve the utilization efficiency of water resources in Manas River Basin, this paper investigated the trends and periods of runoff based on the runoff and climate data for the past 50 years. Subsequently, with the socioeconomic and water resources data, we studied a comprehensive evaluation on the water security in this area. The results indicated that the stream flows in the three hydrological stations of Hongshanzui, Kensiwat and Bajiahu have sig- nificantly increased and undergone abrupt changes, with periods of 18 and 20 years. According to assessment, water security in the Manas River Basin was at an unsafe level in 2008. In criterion layer, the ecological security index and the index of supply-demand situation are both at the relatively secure level; the quantity index and so- cioeconomic index of water resources are at the unsafe level and basic security level, respectively. Therefore, in order to achieve sustainable economic and social development within the Manas River Basin, it is vital to take a series of effective measures to improve the status of water security. 展开更多
关键词 surface runoff processes period and trend sustainable utilization water resources the Manas River Basin fuzzycomprehensive evaluation
下载PDF
Box-Behnken设计-效应面法优化根皮素纳米结构脂质载体处方研究 被引量:10
20
作者 杨金枝 赵兴业 +1 位作者 周开 张智强 《中国医院药学杂志》 CAS 北大核心 2021年第20期2076-2081,共6页
目的:Box-Behnken设计-效应面法优化根皮素纳米结构脂质载体处方。方法:乳化超声法制备根皮素纳米结构脂质载体,采用包封率(Y1)和粒径(Y2)作为考察指标,选择脂-药比(X1)、固液脂质比(X2)、表面活性剂浓度(X3)为主要影响因素,通过二次多... 目的:Box-Behnken设计-效应面法优化根皮素纳米结构脂质载体处方。方法:乳化超声法制备根皮素纳米结构脂质载体,采用包封率(Y1)和粒径(Y2)作为考察指标,选择脂-药比(X1)、固液脂质比(X2)、表面活性剂浓度(X3)为主要影响因素,通过二次多元回归模型拟合根皮素纳米结构脂质载体的影响因素与响应值之间的关系,绘制模型效应面图,并验证最佳处方。结果:最佳处方为:脂-药比为16.4,固液脂质比为4.7,表面活性剂浓度为1.3%。所得3批根皮素纳米结构脂质载体包封率分别为85.7%、84.9%和85.1%;粒径分别为166.9 nm、168.4 nm和170.3 nm,与模型预测值接近。制备的根皮素纳米结构脂质载体基本外貌为圆形,无粘连现象。根皮素存在状态由结晶态转变为无定型态。体外释药具有明显的缓释特征,释药过程符合Weibull模型。结论:Box-Behnken实验设计可用于根皮素纳米结构脂质载体处方的筛选,为后续体内外研究奠定了基础。 展开更多
关键词 根皮素 纳米结构脂质载体 缓释特征 Box-Behnken设计-效应面法
原文传递
上一页 1 2 5 下一页 到第
使用帮助 返回顶部