面粉中含砂量测定的不确定度评定

本文依据《粮油检验粉类粮食含砂量测定》对面粉中含砂量进行测量,并对其测量结果进行不确定度分析,探究影响测量过程中不确定度分量来源并进行评定。分析得出,扩展不确定度为0.0004%,面粉中含砂量测定结果为0.017%±0.0004%(k=2)。     

饲料中镉含量的测量不确定度评定

分析石墨炉原子吸收光谱法测定饲料中镉含量不确定度各个分量,对其测量不确定度进行合理评定,结果表明:饲料样品中镉含量为0.052 mg/kg时,其扩展不确定度为0.0035 mg/kg(k=2),校准过程和测试过程随机效应是引入不确定度的主要原因。     

食品中金黄色葡萄球菌定量检测的不确定度评定

为提高食品中金黄色葡萄球菌定量检测结果的准确性,本文对测量不确定度进行分析和评定。按照《食品安全国家标准食品微生物学检验金黄色葡萄球菌检验》(GB 4789.10—2016)第二法金黄色葡萄球菌平板计数法对人工染菌的乳粉样品进行检测,按照《测量不确定度评定与表示》(JJF 1059.1—2012)分析不确定度来源、评定标准不确定度、计算合成标准不确定度和扩展不确定度。金黄色葡萄球菌定量检测结果的扩展不确定度U=0.066 2(k=2.26),金黄色葡萄球菌定量检测结果为33 574～45 541 CFU·g~(^-1),修约后为34 000～46 000 CFU·g^-1。对金黄色葡萄球菌检测不确定度贡献最大的是接种Baird-Parker平板引入的不确定度,其次是重复检测引入的不确定度。     

中国水稻生产效率的变动分析

一、引言中国是世界最大的稻谷生产国 ,水稻是中国最主要的粮食作物。我国加入WTO后 ,在市场经济的调节下 ,稻谷生产与贸易受国际市场和价格的影响越来越大 ,因而如何保护我国的农业 ,提高我国水稻的国际竞争力 ,促进我国农产品的生产和贸易 ,是摆在我们面前的一件重要事情。而生产效率的提高有助于提高我国水稻的国际竞争力 ,所以 ,研究水稻的生产效率很有意义和价值。生产效率是指产出量与全部投入之比 ,表明产出量的变动与全部投入量变动的关系 ,以衡量生产率的变化对经济增长的作用。生产效率一般是指生产系统的总要素生产率 (TotalFa…     

明代华北农业发展的推动因素分析——生产要素角度的描述与估计

本文以明代时期的北直隶、山东、河南为例,从生产要素的角度分析明代华北农业发展的推动因素.一是人口的增长、迁移和耕地面积的增加.二是农田水利,除了治理河流,井灌得到了广泛采用.三是农业技术有所进步.本文还尝试用生产函数模型,分别对中性、劳动增强型和土地增强型的技术进步率进行估计,结苯表明,明代华北农业的增长方式主要依赖于劳动和耕地的增加.在资源约束日益加剧的今天,要进一步重视技术进步在推动农业发展中的作用,同时在技术选择和创新中还特别需要注意与各地的资源禀赋条件相适应.     

分光光度法测定食品中亚硝酸盐不确定度评估

本文根据《测量不确定度评定与表示》(JJF 1059.1—2012)和《食品安全国家标准食品中亚硝酸盐与硝酸盐的测定》(GB 5009.33—2016),利用分光光度法对食品中亚硝酸盐的含量进行测定,建立数学模型对亚硝酸盐含量测定的不确定度来源分量进行计算、分析,食品中亚硝酸盐的测定结果可以表示为X=(11.2±0.70)mg·kg^-1,k=2,为评价试验测量结果的真确性提供科学依据。     

农地生产率变化及不同规模农户农地生产率比较研究--浙江省农村固定观察点农户农地经营状况分析

本文以浙江省农村固定观察点的农户为研究对象①,对近十几年来农户农地利用结构和生产效率方面的变化做一实证分析。一、农地生产率变化分析(一)农地生产率及其经营效益变化从观察户的跟踪观察资料看,随着科学技术的进步和农户生产技术水平的提高,农户的农地生产率总体呈上升趋势。这里我们以浙江的主要农作物粮食的单位面积产量与农地单位面积投工两个方面来说明。从表1可见,在固定观察点建立以来的14年中,按播种面积计算的粮食亩产提高了15.14%(1988年较1986年提高20.60%);同期,每亩农地的用工量减少了36.76%。表1的后半部分是农户农地经…     

重庆缙云山旅游竞争力提升研究

缙云山作为国家级重点风景名胜区,在自然资源、生态、区位和宗教旅游方面具有一定的旅游竞争优势,但如何有效利用这些优势资源提高景区的竞争力仍是其面临的重要问题。通过分析缙云山的旅游竞争力基本要素,指出其目前存在的旅游产品单一、景区客源市场小等问题。提出改变旅游资源开发方向,完善解说系统,培养专业人才,加强管理等提升缙云山旅游竞争力的相关措施。     

Evaluation of forestland use in mining operation activities in Turkey in terms of sustainable natural resources

Mining has been necessary for human activities and is conducted in line with this need. The location of mines must sometimes be where land use overlaps with other activities because the location of the mined substance cannot be changed. In Turkey, forestland are the most common of these overlapping areas. Therefore, mining has frequently occurred on forestland in Turkey—and worldwide. After the mining operation activities are conducted, the forestland are rehabilitated and returned to the forest administration. The examination of used and returned areas provides an opportunity to create an optimal situation between “mining for sustainable development” and “protection of forestland.”Accordingly, several questions, such as mining production amounts, degrees of social and economic development of the cities in which enterprises are conducting mining, the quantity of the areas they used for mining activities in forestland, the areas which were returned to the forest administration, operating license areas and operation permit areas, and the life of mining operation, were asked to the mining enterprises in Turkey through the “Survey Monkey” program in 2018. Thus, according to mineral groups, different land use rates were compared with the operating license areas, and the land uses for each mineral group were analyzed by considering the operation activity periods. The results indicate that the sustainability of the use of forestry in mining activities in Turkey has changed in a positive direction, particularly because of changes in mining and environmental legislation in Turkey over the last decade.     

Assessment of implementation of protection of mineral deposits in spatial planning in Poland

A complex of raw materials available in a given commune shapes its functional − spatial structure and affects local economic development. The use of the resource base of minerals depends largely on the management of the space and respecting the zoning restrictions connected with protection of mineral deposits. The urgent need to protect them is due to their non-renewable nature and progressive development of the land. Preserving access to deposits is essential to ensure future mineral supply necessary for the economic development. This article presents the results of the assessment of implementation of rules of protection of mineral deposits in spatial planning at the level of territorial units in Poland.The study has been conducted in twenty-three communes of the Lesser Poland voivodeship, for thirty-one unexploited mineral deposits designated for protection in the Spatial Development Plan of the Lesser Poland (Małopolskie) Voivodeship of 2003. In the study of conflict with development of the selected mineral deposits with the environment, factors related to land use, forms of nature protection, water conservation and planned land development have been evaluated. The assessment has taken into account the importance of individual factors of conflict by giving them weights by means of pairwise comparison method. Five classes of conflict of the deposit management have been proposed: non-conflicting deposit, small conflict, medium conflict, major conflict and very big conflict. Almost equal numbers of deposits (9) belong to the class characterized by a of medium, small and large conflicts. Road and technical projects as well as expected significant impact of exploitation on the environment restrain exploitation. The impact is related to the necessity of use of explosives during the exploitation and by the cumulative effect of the mining activity already existing nearby. Analysis of the planning documents of the communes has shown both inadequate protection of mineral resources, including designation of areas of deposits for single-family housing, and a few examples of properly maintained spatial planning in the field of protection of mineral deposits. Information obtained from the environmental survey has been supplemented by assessment of the social aspect. In nine communes it has been determined that the areas of mineral deposits are not subject to spatial conflicts but in seven communes there is opposite situation. The most important benefits from the mineral exploitation which has been indicated in the studied documents included: jobs, access to construction materials and development of the commune.Present work allowed to define the areas and the scale of conflicts induced by development of mineral deposits and to propose measures for rational management of mineral resources. Recognition of the existing and potential conflicts can help to make the right decisions concerning development of the area and minimising impacts of exploitation of the mineral deposits.     

成都“试验区”建设中的农村土地产权流转制度创新——以成都市温江区“两股一改”为例

全国统筹城乡综合配套改革试验区建设,必然要求成都着力打破城乡二元经济结构,促进城乡生产要素有效流动.在该探索过程中,温江区提出了地产权流转为主要特征的"两股一改"模式,并以此来破除城乡二元结构、形成城乡经济社会发展一体话新格局.本文将对这一模式的主要做法进行介绍,并试图对其蕴涵和预示的制度创新、理论价值、发展趋势进行探讨.     

中国市场化改革进程中农业发展的若干趋势

我国国民经济和社会发展跨入 2 1世纪新的历史时期 ,将出现的结构转型、体制转轨和对外经济开放的三大趋势 ,对我国农业发展将带来深远的影响。在这里 ,我们尚难清晰地描绘中国农业发展未来走向的全貌 ,但从市场化改革进程中已经发生的或者已经初见端倪的若干变化 ,可以大致地勾勒出市场经济条件下中国农业发展的背景条件 ,这些显著的变化 ,总的集中体现在由产品经济向市场经济的转变 ,具体则体现在 :农业投资主体由以集体为主转向农户个体为主 ;农业生产组织由行政性安排转向农民自组织 ;农产品交易由行政性分割市场转向国内统一大市场 ;农…     

试析牛对清代台湾乡村社会发展的贡献

清代台湾社会开发的主力军是闽粤移民，但牛在乡村社会的发展中，充当了极重要的生产力角色。牛在台湾乡村社会的土地开垦与工商业发展中独当一面，在民众生活甚至风俗中也占显要位置。牛是清代台湾乡村社会发展过程中不可缺少的重要动力。     

我国水利多种经营发展现状综述

简述我国水利多种经营总体概况和现状，分析水利多种经营产业结构、产业经济效益、优势产业、资产规模、资产质量和资产效率，比较全国水利多种经营的地区发展差距，从总体上评价水利多种经营发展现状，分析我国水利多种经营发展现状的成因。得出结论：水利多种经营工作的成效是显著的，进一步发展水利多种经营的潜力是巨大的。     

天津市七里海滨海湿地沉积物重金属元素的空间分布特征

对七里海滨海湿地沉积物6种重金属元素进行系统分析,结果表明Cu、Zn、Pb、As、Cd 5种元素在沉积物中含量相对稳定,Hg元素在湿地沉积物中分布不均匀,变化较大。富集度分析表明,七里海滨海湿地重金属富集度划分为元素适中、轻度富集、中度富集3个级别,元素富集程度依次为Cd＞Cu＞Zn＞Pb＞Hg＞As,As元素基本介于元素适中和元素贫乏之间, Cu、Zn、Pb、Hg 4种重金属达到了轻度富集,说明该区已受到轻度污染,Cd元素已到达中度富集,说明该区已受到中度污染,应引起重视。     

信托制度在促进我国林木保险发展中的应用

我国在促进林木保险发展时主要采取补贴方式,具体分为向林农补贴和向保险公司补贴两种方法.经过分析,认为直接对二者进行补贴效果较差,提出了信托制度作为第三方参与到林木保险发展中的设想.通过明确委托人(政府)、受托人(信托公司)以及受益人(林农)在信托运作时的权利与义务,认为信托制度可以规范并整合保险需求,鼓励保险公司涉入林木保险业务,促进我国林木保险发展,并逐步缓解政府相关的财政压力.最后,提出信托制度在具体应用时的注意事项.     

茜素红在食品硼酸检测中的应用研究

本文通过对硼酸与茜素红显色的研究,开发出了一种简单易行的食品中硼酸检测的荧光分光光度法.结果表明,该方法使用茜素红与硼酸在甲醇水反应体系中形成高灵敏的荧光显色反应,利用纯有机试剂提取降低样品中水溶性荧光干扰物的影响,其样品添加回收率在79.6％～116.0％,检测结果准确可靠.     

黑龙江省制造业企业技术创新对策研究

对黑龙江省制造业技术创新现状、存在问题以及解决对策从理论和实例两个方面进行较为系统的研究。首先阐述了制造业进行技术创新的目的和意义,分析国内外制造业存在的差距以及未来制造业企业的特点及发展趋势,结合黑龙江省企业技术创新的现状,分析制造业企业在进行技术创新的过程中存在的问题,提出黑龙江省制造业的技术创新战略,并从企业内部和外部两个方面提出了相应的解决对策。     

农用地定级中区位因素定量化存在的问题及其改进

通过介绍目前农用地定级工作中区位因素定量化处理的一般方法,分析了目前区位因素定量化过程中存在的问题,如空间距离量算、阻隔与通道、衰减模型、定级区域外的区位因素影响等,并提出了相应的改进措施,以使定级结果尽可能的符合实际.     

"用斗钱运斗米"辨--关于唐代漕运江南租米的费用

本文针对唐人关于漕运江南租米入京的费用达“用斗钱运斗米”的程度的说法 ,试作量化分析 ,认为唐代江南漕运的费用 ,在不同时期有显著不同。在费损率高达 80 %的特定条件下 ,其费用可能会达到以“斗米费斗钱”的程度 ;正常情况下 ,其费用多维持在每斗二三百文之间 ,最低可至七八十文。所谓“用斗钱运斗米”在多数场合确实属于“流俗过言”