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新疆野生植物资源——芦苇多用化研究 被引量:15
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作者 刘明智 努尔巴衣.阿布都沙力克 +1 位作者 江凌 潘晓玲 《农业科学研究》 2005年第1期76-79,共4页
芦苇是广布世界的水生植物,中国有卡开芦苇(南方大苇)等芦苇8种,新疆芦苇主要是普通芦苇,在长期适应干旱环境的过程中,分化形成了不同的生态类型,即水生芦苇(水芦或大芦苇)、盐化草甸芦苇(盐芦或小芦苇)、沙丘芦苇(沙芦或中芦苇)、水生... 芦苇是广布世界的水生植物,中国有卡开芦苇(南方大苇)等芦苇8种,新疆芦苇主要是普通芦苇,在长期适应干旱环境的过程中,分化形成了不同的生态类型,即水生芦苇(水芦或大芦苇)、盐化草甸芦苇(盐芦或小芦苇)、沙丘芦苇(沙芦或中芦苇)、水生向陆生的过渡芦(过渡芦或中芦苇)等.是可再生的生物资源,具有较高的经济和社会生态价值.干旱区的新疆芦苇资源丰富,在有水处生长着繁茂的株高3~5 m的大芦苇,无水或地下水位一般为2~5 m的较高处生长有株高1~2.5 m的过渡芦,甚至在沙丘上亦有株高1.5~2 m的沙芦生长,即使盐渍化极为严重、地表盐积壳厚达1~5 cm的地方,除偶有耐盐碱的柽柳生长外,茫茫盐碱滩生长最多的是成片株高0.2~1 m的盐芦.开发利用好这一资源,使这一资源多用化,既能带动新疆的经济腾飞,促进畜牧业发展,又能为产业结构的调整提供新的思路,更有利于生态脆弱的新疆的生态环境建设与生态恢复. 展开更多
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Technical efficiency of cocoa farms at varying elevation levels in Davao City, Philippines: implications to sustainable upland farming systems
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作者 Francis Levi A.DURANO Jon Marx SARMIENTO +1 位作者 Larry N.DIGAL Pedro A.ALVIOLA IV 《Journal of Mountain Science》 SCIE CSCD 2024年第1期33-48,共16页
Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa ... Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa farms using cross-sectional data from areas ranging from 190 to 1021 m above sea level which were classified as low, medium, and high elevation in Davao City, considered as the chocolate capital of the Philippines. Using stochastic frontier analysis, the results showed that the cost of inputs per ha and the number of cocoa trees per ha significantly increase yield. Farms at high elevations were less technically efficient, as this entails lower temperatures and increased rainfall, and cocoa farming in those areas and conditions can be more challenging, especially with changes in farming practices, terrain, and distance to markets. Other significant variables were age of cocoa farms, married farmers, and age of the farmers. Older farms may be more developed, farmers who are married benefit from their spouses being able to readily contribute as farm labor, and lastly, older farmers' inefficiency may likely stem from nonadaptation of newer farming practices. With an average technical efficiency of 0.61, 0.63, and 0.26 in low, medium, and high elevation areas, respectively, farmers therefore have an incentive to improve farm practices and consider topographical variations found in high elevation areas. Recommendations for the improvement of technical efficiency of cocoa farms are better connectivity to markets, enhancing farm practices, and continuation and improvement of government programs on cocoa with an added emphasis on research. For farmers in high elevation areas, mitigating solutions such as sustainable agriculture practices and ecolabelling are key to improving efficiency and minimizing the potential negative impact on upland farming systems. Moreover, such adaptation measures may also contribute to sustainability of cocoa farming in high elevation areas. 展开更多
关键词 Cocoa farms Cobb-Douglas production function ELEVATION Philippines Stochastic frontier analysis technical efficiency
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公用事业民营化的行政法思考 被引量:3
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作者 郭朋 《山东师范大学学报(人文社会科学版)》 北大核心 2005年第1期62-66,共5页
 公用事业民营化改革对我国行政法治建设和宪政制度建设具有良性推动作用。公用事业民营化改革的关键是处理好政府角色、功能的合理定位问题,同时要处理好政府、公用事业企业、消费者三方的关系。具体途径是设立独立的管制机构,实现政...  公用事业民营化改革对我国行政法治建设和宪政制度建设具有良性推动作用。公用事业民营化改革的关键是处理好政府角色、功能的合理定位问题,同时要处理好政府、公用事业企业、消费者三方的关系。具体途径是设立独立的管制机构,实现政府从公用事业的垄断经营者向竞争性经营的组织者的角色转变;积极落实政府信息公开和听证制度,实现政府管制程序的法治化;要从完善公共财政制度建设着手,进一步规范政府对公用事业领域的财政支出;要积极打造诚信政府,强化和完善政府责任的落实和追究。 展开更多
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ISO Certification and Technical Efficiency in the Banking Sector:An Evidence from WAEMU’s Countries Using the DEA Method
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作者 Gnoleba Martin Zahore 《Economics World》 2024年第2期55-68,共14页
In the view of the international organization of standardization,the introduction of ISO standards is typical of quality management systems oriented towards strengthening the efficiency of enterprises.Business banks a... In the view of the international organization of standardization,the introduction of ISO standards is typical of quality management systems oriented towards strengthening the efficiency of enterprises.Business banks are not excluded from this requirement.The current study aims to evaluate the effect of ISO certification on the technical performance of WAEMU banks.Using BCEAO data(2020),the DEA model and Tobit estimates show that ISO certification has no effect on the efficiency scores of the banks in the sample.It is therefore appropriate for these banks to work on improving their business climate. 展开更多
关键词 business banks DEA technical efficiency ISO WAEMU TOBIT
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Digital Economy: A Vision From The Future
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作者 Valentina Bondarenko 《Journal of Economic Science Research》 2020年第1期16-23,共8页
The article shows that the foundation of the digital economy can be a new paradigm for predicting the future from the future,i.e.from the future in which the development goal has already been achieved.This allows to m... The article shows that the foundation of the digital economy can be a new paradigm for predicting the future from the future,i.e.from the future in which the development goal has already been achieved.This allows to minimize all costs and completely avoid incorrect system solutions of the existing trial-and-error approach.Using the achievements of the technological revolution of Industry 4.0,an effective digital economy can be formed only when it is seen as an economy of coordinated interests between the state,business,society and the interests of each individual in real time at every local level.This will make it possible to solve the problem of ensuring the high quality of life not of citizens in general,but of each individual. 展开更多
关键词 Glushkov VM OGAS Scientific and technical progress Industry 4.0 Digital economy CRISIS New methodological tools GOAL Complexity Integrity CONSISTENCY Interdisciplinarity A SINGLE indicator A SINGLE criterion of efficiency Forecasting the FUTURE from the FUTURE
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长江城市岸线资源港口开发适宜性分析与合理利用——以南京市为例 被引量:35
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作者 朱红云 杨桂山 +1 位作者 万荣荣 马荣华 《长江流域资源与环境》 CAS CSSCI CSCD 北大核心 2005年第4期404-408,共5页
城市岸线地区是城市中具有巨大发展潜力的空间领域,在城市发展的不同时期承担着不同的功能。农业社会对岸线的利用规模小,工业革命以后,城市岸线地区成为主要的港口(含公用港口和工业用港口)集聚地段之一。随着经济的发展和生活水平的提... 城市岸线地区是城市中具有巨大发展潜力的空间领域,在城市发展的不同时期承担着不同的功能。农业社会对岸线的利用规模小,工业革命以后,城市岸线地区成为主要的港口(含公用港口和工业用港口)集聚地段之一。随着经济的发展和生活水平的提高,人们赋予城市岸线的利用功能不断增加。仅从岸线自然条件及岸线集疏运、城市依托等人文因素出发讨论岸线港口开发适宜性的做法已无法适应发展的需要。只有统筹考虑岸线承担的多种功能,才能实现岸线地区经济和生态的双赢。以长江南京段岸线为例,从岸线自然条件和岸线承担的多种功能角度,分析了岸线资源港口开发的适宜性状况,指出岸线利用存在的主要问题,在此基础上提出城市岸线资源合理开发利用和保护的对策建议。 展开更多
关键词 线 线
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我国LNG工厂的生产流程介绍 被引量:17
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作者 曹文胜 鲁雪生 +2 位作者 顾安忠 石玉美 汪荣顺 《天然气工业》 EI CAS CSCD 北大核心 2005年第5期100-102,121,共4页
介绍了我国的LNG示范装置、调峰型工厂和基本负荷型工厂的状况,包括这些装置和工厂的生产规模和工艺流程。这些流程包括:级联式、混合制冷剂、带膨胀机的液化流程制冷,并比较了各自的使用特点和优劣。最后指出了我国LNG工厂的发展方向:... 介绍了我国的LNG示范装置、调峰型工厂和基本负荷型工厂的状况,包括这些装置和工厂的生产规模和工艺流程。这些流程包括:级联式、混合制冷剂、带膨胀机的液化流程制冷,并比较了各自的使用特点和优劣。最后指出了我国LNG工厂的发展方向:根据国情,依据具体的设计条件和外围条件,对不同液化流程的投资成本、比功耗、运行要求进行全面的对比分析;要紧跟当前天然气液化流程追求简便、高效的发展趋势,综合考虑各种液化流程的技术特点,开发适合我国实际情况的新型液化流程———流程精简、设备少,冷箱结构紧凑,换热效率高,火用损小,压缩机和驱动机高效、可靠,应大力发展具有调峰、机动能力的中、小型LNG装置,以适应我国已经面临大规模开发利用天然气的新形势。 展开更多
关键词 LNG
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中国优质蛋白玉米育种研究进展 被引量:12
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作者 杨晓辉 韩晓清 崔书会 《北京农学院学报》 2005年第1期71-75,共5页
随着中国居民收入的不断提高,人们的饮食结构有了较大的改善,市场对畜产品的需求量大大增加。高赖氨酸玉米的出现,标志着玉米不再是单纯的热能饲料,而是热能与蛋白质相结合的新型饲料;然而,纯隐性的高赖氨酸玉米粉质胚乳表现出的生理缺... 随着中国居民收入的不断提高,人们的饮食结构有了较大的改善,市场对畜产品的需求量大大增加。高赖氨酸玉米的出现,标志着玉米不再是单纯的热能饲料,而是热能与蛋白质相结合的新型饲料;然而,纯隐性的高赖氨酸玉米粉质胚乳表现出的生理缺陷,制约了高赖氨酸玉米的发展与利用。中国育种工作者经过30年的艰苦努力,将纯隐性的高赖氨酸玉米改良成半硬质、硬质胚乳的高赖氨酸玉米自交系,组配出胚乳籽粒半硬质的高赖氨酸玉米杂交种;随着人们对优质蛋白玉米品质、利用价值、饲用价值、经济价值认识不断提高,如能得到政府的重视和扶持,优质蛋白玉米将在中国的种植业、畜牧业中发挥其应有的作用。 展开更多
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Construction of a nomogram model to predict technical difficulty in performing laparoscopic sphincter-preserving radical resection for rectal cancer
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作者 Xiao-Cong Zhou Shi-Wei Guan +3 位作者 Fei-Yue Ke Gaurav Dhamija Qiang Wang Bang-Fei Chen 《World Journal of Gastroenterology》 SCIE CAS 2024年第18期2418-2439,共22页
BACKGROUND Colorectal surgeons are well aware that performing surgery for rectal cancer becomes more challenging in obese patients with narrow and deep pelvic cavities.Therefore,it is essential for colorectal surgeons... BACKGROUND Colorectal surgeons are well aware that performing surgery for rectal cancer becomes more challenging in obese patients with narrow and deep pelvic cavities.Therefore,it is essential for colorectal surgeons to have a comprehensive understanding of pelvic structure prior to surgery and anticipate potential surgical difficulties.AIM To evaluate predictive parameters for technical challenges encountered during laparoscopic radical sphincter-preserving surgery for rectal cancer.METHODS We retrospectively gathered data from 162 consecutive patients who underwent laparoscopic radical sphincterpreserving surgery for rectal cancer.Three-dimensional reconstruction of pelvic bone and soft tissue parameters was conducted using computed tomography(CT)scans.Operative difficulty was categorized as either high or low,and multivariate logistic regression analysis was employed to identify predictors of operative difficulty,ultimately creating a nomogram.RESULTS Out of 162 patients,21(13.0%)were classified in the high surgical difficulty group,while 141(87.0%)were in the low surgical difficulty group.Multivariate logistic regression analysis showed that the surgical approach using laparoscopic intersphincteric dissection,intraoperative preventive ostomy,and the sacrococcygeal distance were independent risk factors for highly difficult laparoscopic radical sphincter-sparing surgery for rectal cancer(P<0.05).Conversely,the anterior-posterior diameter of pelvic inlet/sacrococcygeal distance was identified as a protective factor(P<0.05).A nomogram was subsequently constructed,demonstrating good predictive accuracy(C-index=0.834).CONCLUSION The surgical approach,intraoperative preventive ostomy,the sacrococcygeal distance,and the anterior-posterior diameter of pelvic inlet/sacrococcygeal distance could help to predict the difficulty of laparoscopic radical sphincter-preserving surgery. 展开更多
关键词 NOMOGRAM Rectal cancer Laparoscopic operation Sphincter-preserving surgery technical difficulty
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基于自助法的中国水电能资源开发利用Logistic预测 被引量:7
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作者 汪哲荪 金菊良 +2 位作者 魏一鸣 周玉良 杨希凡 《水电能源科学》 北大核心 2010年第10期151-153,共3页
基于近20 a中国水电装机容量序列,采用加速遗传算法构建了Logistic预测模型,并运用自助法对Logistic预测模型的误差进行重抽样,提出了基于自助法的中国水电能资源开发利用Logistic预测模型(BLP-HPU),预测了2015、2020年中国水电能资源... 基于近20 a中国水电装机容量序列,采用加速遗传算法构建了Logistic预测模型,并运用自助法对Logistic预测模型的误差进行重抽样,提出了基于自助法的中国水电能资源开发利用Logistic预测模型(BLP-HPU),预测了2015、2020年中国水电能资源开发利用预测值的置信区间。实例结果表明,该模型物理概念清晰、计算简便、预测精度高,在风能等可再生能源资源开发利用预测中具有推广应用价值。 展开更多
关键词 LOGISTIC BOOTSTRAP Method Based China RESOURCES Utilization Power
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不同利用方式与坡位土壤物理性质及养分特征分析 被引量:148
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作者 高雪松 邓良基 张世熔 《水土保持学报》 CSCD 北大核心 2005年第2期53-56,60,79,共6页
以四川盆地西缘山地的典型坡面为材料,研究了不同土地利用方式和地形部位条件下土壤物理性质和养分的分异特征,结果表明,3个坡面地形部位(上坡位,中坡位,下坡位) ,下坡位土壤物理结构性能较好,而人工林与坡耕地、荒草地相比较,人工林更... 以四川盆地西缘山地的典型坡面为材料,研究了不同土地利用方式和地形部位条件下土壤物理性质和养分的分异特征,结果表明,3个坡面地形部位(上坡位,中坡位,下坡位) ,下坡位土壤物理结构性能较好,而人工林与坡耕地、荒草地相比较,人工林更能增强土壤的结构性。土壤养分分异特征表明,在不同利用类型条件下,土壤有机质、氮素和阳离子交换量CEC在人工林中含量最高,且与其他两种利用类型中的含量差异显著,有机质、碱解氮和CEC三者含量差异达到极显著水平。相关分析表明,土壤表层有机质、全氮、碱解氮呈极显著正相关。而坡面位置中,与上坡位,中坡位相比,下坡位土壤养分含量普遍要高,其中CEC含量差异达到极显著水平,相关分析表明,CEC与土壤粘粒呈极显著正相关。 展开更多
关键词 CEC
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我国人心果的品种资源、生产现状及发展对策 被引量:15
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作者 谢碧霞 文亚峰 +1 位作者 何钢 梁文斌 《经济林研究》 2005年第1期1-3,共3页
人心果是一种具有广泛用途的热带果树,具有十分重要的开发利用价值。调查结果表明,我国人心果资源主要分布于广西中南部、云南广东福建省南部及海南、台湾等地,可划分为3个大的栽培区域。栽培品种根据果实形状不同,可分为椭圆形果、圆... 人心果是一种具有广泛用途的热带果树,具有十分重要的开发利用价值。调查结果表明,我国人心果资源主要分布于广西中南部、云南广东福建省南部及海南、台湾等地,可划分为3个大的栽培区域。栽培品种根据果实形状不同,可分为椭圆形果、圆形果和圆锥形果3大类。人心果资源稀少、良种缺乏,尚未形成规模化商业性栽培,加工利用亦未起步。针对目前现状,提出了引进并加快良种繁育、建立高水平科技示范园、开展分类研究及培育良种、开展果胶提取与加工技术研究的发展对策。 展开更多
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A STUDY ON THE TECHNICAL PROPERTIES OF PEPSET NO-BAKE RESIN-BONDED SAND AND FACTORS HAVING INFLUENCE
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作者 杨晶 赵丽萍 程军 《兵工学报》 EI CAS CSCD 北大核心 2000年第1期-,共3页
通过试验研究了PEPSET树脂自硬砂工艺应用于铝铸件生产的性能及其影响因素。指出 PEPSET 树脂自硬砂工艺在硬化速度、流动性、发气性、溃散性等方面性能良好, 利于复杂铝铸件的造型制芯,有望成为树脂自硬砂工艺的一个重要发展方向。
关键词 PEPSET A STUDY ON THE technical PROPERTIES OF PEPSET NO-BAKE
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Solvothermal synthesis and adsorption performance of layered boehmite using aluminum chloride and high-alumina fly ash
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作者 Jing Wen Ruirui Yuan +2 位作者 Tao Jiang Tangxia Yu Yufan Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第6期280-290,共11页
High alumina fly ash(FAHAl)is a kind of bulk solid waste unique to China,whose availability of high-value aluminum and the threat to the environment makes its high-value utilization urgent.In this work,the alumina con... High alumina fly ash(FAHAl)is a kind of bulk solid waste unique to China,whose availability of high-value aluminum and the threat to the environment makes its high-value utilization urgent.In this work,the alumina containing leaching solution obtained from Na2CO_(3) roasting and HCl leaching of FAHAl was used as the mother liquor to prepare layered boehmite in situ.The preparation process with AlCl3 as the raw material was also compared.The formation process and mechanism of boehmite,the choice of solvent,along with the adsorption capability of Congo red were analyzed by X-ray diffraction,scanning electron microscopy,Fourier transform infrared spectroscopy,Brunauer-Emmett-Teller method and adsorption experiments.Results showed that during the preparation of layered boehmite,the precursor Al(OH)3 from the reaction of Al3+and OH-is transformed into boehmiteγ-AlOOH.The existence of ethanol is beneficial to regulate and promote the growth of boehmite crystal effectively.When water and ethanol are mixed with a volume ratio of 2:1 and used as the solvent,the maximum specific surface area of the boehmite is obtained at 135.7 m2·g^(-1),and 99.16%of Congo red can be absorbed after 10 min when AlCl3 is used as a raw material.As purified leaching solution is used as the mother liquid,the crystallinity of boehmite decreases slightly when the pH value decreases from 12.5 to 11.When pH is 11,the removal efficiency of Congo red reaches a maximum of 72.25%.This process not only achieves the extraction of aluminum and high-value utilization of FAHAl but also provides a thought to prepare layered boehmite with adsorption properties. 展开更多
关键词 HIGH-ALUMINA FLY ash LAYERED BOEHMITE In-situ preparation SOLVOTHERMAL synthesis Adsorption High-value utilization
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福州市土地利用景观格局动态分析 被引量:5
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作者 郑丽丹 黄曦 +2 位作者 叶夏 陈志彪 陈志强 《江西农业学报》 CAS 2010年第10期138-140,143,共4页
在GIS和Fragstats的软件技术支持下,以1988年和2008年福州市两期的土地利用图为数据源,对福州市的土地利用类型及其景观格局指数进行统计分析。结果表明,20年来福州地区的土地利用景观类型以耕地、林地和建设用地为主,土地利用变化主要... 在GIS和Fragstats的软件技术支持下,以1988年和2008年福州市两期的土地利用图为数据源,对福州市的土地利用类型及其景观格局指数进行统计分析。结果表明,20年来福州地区的土地利用景观类型以耕地、林地和建设用地为主,土地利用变化主要是耕地、林地和水体转化为建设用地。斑块数量和斑块密度增加,景观破碎化程度加剧,多样性指数上升,优势度下降,景观格局趋于均质稳定化。斑块聚集度下降,向离散化方向发展,景观蔓延度也降低,进而反映了人为活动对土地利用变化的影响。 展开更多
关键词 Fuzhou City LANDSCAPE Pattern Land Utilization FRAGSTATS
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Study of The Technical Index of Online Learning Behavior Analysis of Nursing Majors on The Superstar Platform Based on The Kirkpatrick Evaluation Model
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作者 Yi Zhang Xiaohua Zhao Jie Li 《Journal of Clinical and Nursing Research》 2024年第4期284-291,共8页
Objective:To analyze the technical indexes of students’online learning behavior analysis based on Kirkman’s evaluation model,sort out the basic indexes of online learning behavior,and extract scientific and efficien... Objective:To analyze the technical indexes of students’online learning behavior analysis based on Kirkman’s evaluation model,sort out the basic indexes of online learning behavior,and extract scientific and efficient evaluation indexes of online learning effect through statistical analysis.Methods:The online learning behavior data of Physiology of nursing students from 2021-2023 and the first semester of 22 nursing classes(3 and 4)were collected and analyzed.The preset learning behavior indexes were analyzed by multi-dimensional analysis and a correlation analysis was conducted between the indexes and the final examination scores to screen for the dominant important indexes for online learning effect evaluation.Results:The study found that the demand for online learning of nursing students from 2021-2023 increased and the effect was statistically significant.Compared with the stage assessment results,the online learning effect was statistically significant.Conclusion:The main indicators for evaluating and classifying online learning behaviors were summarized.These two indicators can help teachers predict which part of students need learning intervention,optimize the teaching process,and help students improve their learning behavior and academic performance. 展开更多
关键词 Kirkpatrick assessment model Superstar platform Online learning behavior Analyzing technical indicators Research
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Discussion on the Application of Technical and Tactical Skills in Mixed Martial Arts Competitions
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作者 Yu Huang 《Journal of Contemporary Educational Research》 2024年第2期8-13,共6页
This article mainly analyzes the application of technical and tactical skills in mixed martial arts competitions,including mixed martial arts and its competition characteristics,the main application significance of te... This article mainly analyzes the application of technical and tactical skills in mixed martial arts competitions,including mixed martial arts and its competition characteristics,the main application significance of technical and tactical skills in mixed martial arts competitions,and its primary application strategies.It is hoped that this analysis can provide some guidelines for the appropriate application of mixed martial arts athletes’technical and tactical skills to improve their winning rate in mixed martial arts competitions. 展开更多
关键词 Mixed martial arts competition technical and tactical skills Fighting awareness Fighting movements Competition rhythm
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淮北市采煤沉陷区非常规水资源开发利用研究 被引量:16
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作者 张树军 许士国 +4 位作者 高尧 李庆海 吴亚军 郭秀红 曹成立 《水电能源科学》 北大核心 2010年第7期27-30,117,共5页
以淮北市采煤沉陷区为研究对象,在综合分析采煤沉陷区非常规水资源利用可行性的基础上,建立了淮北市采煤沉陷区"一河两区"的非常规水资源利用系统。运用情景分析法组合构建了18种未来可能情景,采用典型年水量均衡法计算得到... 以淮北市采煤沉陷区为研究对象,在综合分析采煤沉陷区非常规水资源利用可行性的基础上,建立了淮北市采煤沉陷区"一河两区"的非常规水资源利用系统。运用情景分析法组合构建了18种未来可能情景,采用典型年水量均衡法计算得到了不同情景下沉陷区的供水保证率。研究结果表明,通过采煤沉陷区的调蓄,境内非常规水资源可利用量相当可观,在丰水年份可满足工业园用水要求,平、枯水年份工业园用水保证率也有很大提高。通过采煤沉陷区的非常规水资源利用,可提高淮北市的水资源利用效率,有效应对淮北市面临的水资源短缺问题,保障社会经济的可持续发展。 展开更多
关键词 Mining Subsidence Water Resources Utilization
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Quality Standard of Tibetan Medicine Nardostachys jatamansi Herba Based on"An Integrated Plant but Multi-purpose"
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作者 Hairong ZHONG Yuebu HAILAI +2 位作者 Shaoshan ZHANG Wenbing LI Yuan LIU 《Medicinal Plant》 2024年第3期16-22,共7页
[Objectives]To establish the quality standard of Nardostachys jatamansi Herba.[Methods]The characters and microscopical identification of N.jatamansi Herba were carried out.The contents of moisture,total ash,acid-inso... [Objectives]To establish the quality standard of Nardostachys jatamansi Herba.[Methods]The characters and microscopical identification of N.jatamansi Herba were carried out.The contents of moisture,total ash,acid-insoluble ash and extract were determined according to the relevant methods of the Chinese Pharmacopoeia(2020 edition).Using chlorogenic acid and 3,5-O-dicaffeoylquinic acid as quality control indexes,TLC and HPLC methods were established for qualitative and quantitative determination,and HPLC fingerprints were established.[Results]The characteristics of character identification,microscopic identification and thin layer identification were obvious.The moisture content ranged from 2.7%to 7.8%,with an average value of 5.4%.The total ash content ranged from 6.7%to 16.2%,with an average of 11.0%.The acid-insoluble ash content ranged from 0.7%to 8.5%,with an average of 3.6%.Extractives content ranged from 20.9%to 34.4%,with an average of 29.7%.Chlorogenic acid content was between 0.45%and 1.30%,with an average value of 0.77%.The content of 3,5-O-dicaffeoylquinic acid ranged from 0.18%to 0.58%,with an average of 0.31%.The similarity of each batch was between 0.930 and 0.994,indicating that the quality of medicinal materials from different producing areas was stable.[Conclusions]The quality standard of N.jatamansi Herba was established,which could provide quality control basis for rational,comprehensive and efficient utilization of N.jatamansi DC.resources and clinical use. 展开更多
关键词 Nardostachys jatamansi Herba Chlorogenic ACID 3 5-O-dicaffeoylquinic ACID FINGERPRINT Quality standard RESOURCE UTILIZATION
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胜坨油田特高含水期井网重组技术优化研究 被引量:35
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作者 孙国 《油气地质与采收率》 CAS CSCD 北大核心 2005年第3期48-50,共3页
胜坨油田是含油层系多、储层非均质严重的多层砂岩油藏,进入特高含水期后,应用常规层系井网调整技术难以有效挖掘多层砂岩的剩余油潜力,井网重组成为进一步提高采收率的深度开发技术。以胜坨油田坨28块沙二段1-3单元为例,建立概念模型,... 胜坨油田是含油层系多、储层非均质严重的多层砂岩油藏,进入特高含水期后,应用常规层系井网调整技术难以有效挖掘多层砂岩的剩余油潜力,井网重组成为进一步提高采收率的深度开发技术。以胜坨油田坨28块沙二段1-3单元为例,建立概念模型,应用数值模拟技术,开展了井网重组技术优化研究,得出了井网重组时的技术政策界限,包括井网重组后的井网调整方式、不同组合层系的压力保持水平等。以此研究结果为指导开展了坨7 井网重组先导试验。方案实施后,10口新钻油井投产非主力层初期平均单井产油量8.6t/d,比调整前平均单井产油量高2倍;含水率70.6%,比单元综合含水率低25.6%,取得了较好效果。 展开更多
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