全文获取类型
收费全文 | 68篇 |
免费 | 7篇 |
专业分类
林业 | 2篇 |
基础科学 | 1篇 |
2篇 | |
综合类 | 9篇 |
农作物 | 3篇 |
水产渔业 | 6篇 |
畜牧兽医 | 47篇 |
植物保护 | 5篇 |
出版年
2019年 | 4篇 |
2018年 | 2篇 |
2017年 | 2篇 |
2016年 | 1篇 |
2015年 | 1篇 |
2014年 | 1篇 |
2013年 | 2篇 |
2012年 | 3篇 |
2011年 | 1篇 |
2010年 | 2篇 |
2009年 | 5篇 |
2008年 | 2篇 |
2007年 | 2篇 |
2006年 | 2篇 |
2005年 | 7篇 |
2004年 | 1篇 |
2003年 | 3篇 |
2002年 | 4篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 4篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1984年 | 2篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 3篇 |
1975年 | 1篇 |
1971年 | 2篇 |
1948年 | 2篇 |
排序方式: 共有75条查询结果,搜索用时 562 毫秒
11.
12.
M P Van Der Walt J M Van Rooyen G Oberholzer G Van Aswegen 《The Onderstepoort journal of veterinary research》1992,59(2):107-109
The skin of the red-banded rubber frog is said to secrete an unidentified toxin. Whole skin extract as well as HPLC fractions were tested for toxicity on viable, isolated cardiomyocytes. The skin extract and one of its fractions were shown to be cardiotoxic. Whole-cell clamping tests demonstrated that both extract and fraction interfered with the function of the potassium channels of the cardiomyocytes and that the toxic substance has an affinity for the IK, channels. Investigations are in progress to isolate and characterize the toxic substance. 相似文献
13.
J G Van der Walt 《The Onderstepoort journal of veterinary research》1978,45(2):125-131
14.
15.
16.
A fluorescent excitation transfer immunoassay for spinosyn A, a fermentation derived insect control agent, has been developed and applied to the analysis of tap water and wastewater effluent from manufacturing plants. Fluorescein (F) and tetramethylrhodamine (TMR) were chosen as donor and quencher, respectively, for the excitation transfer. Fluorescence quenching was observed from the binding of F-labeled antigen to TMR-labeled antibody. By employing nonlabeled antigen in a competitive immunoassay format, we reversed fluorescence quenching. The assay provides a limit of detection of 0. 01 ppb and a working range of 0.05-1 ppb and allows for the rapid determination of spinosyn A in water with recovery values ranging from 96% to 120%. With the exploitation of the small size of optical fibers, fluorescence from an assay volume of 24 microL could be measured without special vessels. 相似文献
17.
Effect of an intensive mechanical removal effort on a population of non‐native rainbow trout Oncorhynchus mykiss in a South African headwater stream 下载免费PDF全文
Jeremy Shelton Olaf Weyl Johannes Van Der Walt Sean Marr Dean Impson Kristine Maciejewski Donovan Tye Helen Dallas Karen Esler 《水产资源保护:海洋与淡水生态系统》2017,27(5):1051-1055
18.
Conservation implications of establishment success of the Critically Endangered Twee River redfin ‘Pseudobarbus’ erubescens (Skelton, ) in an artificial impoundment in South Africa 下载免费PDF全文
Martine S. Jordaan Johannes A. van der Walt Zanné Brink Sonja Erasmus Olaf L. F. Weyl 《水产资源保护:海洋与淡水生态系统》2017,27(4):886-889
19.
20.
Since its inception, in 1885 the Buckeye Irrigation Canal has delivered irrigation water in the Buckeye Valley, southwest of Phoenix, Arizona. Throughout its tenure the owners of the canal have consulted design professionals for its engineering needs. Early engineering in 1885 established canal alignments, delivery points and channel capacity. Until recently, the Buckeye Valley was a rural area relying on agricultural revenues to drive the local economy. Now, due to the recent housing market boom new homes started springing up like corn in September driving the existing open-channel laterals below grade into a patch work redesigned pipeline system. Because of these changes, professional construction managers are an enormous benefit to the Buckeye Water Conservation and Drainage District (BWCDD), the owner of the canal.As a result of this urbanization, contractors working for home developers are installing irrigation pipelines and systems with the focus of completing the project as quickly and economically as possible. Irrigation providers, on the other hand, focus on meeting the agricultural needs of their clients with consistent and uninterrupted water delivery. The services of a professional construction manager help both entities achieve their respective goals, shield BWCDD from construction of sub-par systems and risk, maintain uninterrupted service to growers and providing the technical expertise to communicate with both BWCDD and contractors.Construction managers provide a number of services to rural irrigation districts under-going urbanization. They team with an irrigation district by:
- Understanding irrigation design concepts;
- Understanding agricultural demands;
- Providing a thorough knowledge of construction practices and standards;
- Creating long-term design functionality;
- Reducing stress on and increasing productivity of personnel;
- Coordinating construction activities with water deliveries;
- Verifying constructed facilities perform as designed, which reduces maintenance costs.
- Reviewing development plans for adherence to current construction standards and practices and coordinates construction schedules with water delivery needs;
- Observing construction for proper installation;
- Clarifying installers understanding of plans and specifications;
- Coordinating interruptions in service;
- Tracking multiple construction projects;
- Explaining agricultural practices to contractor personnel;
- Providing a single point of contact for construction related correspondence.