Results 31 to 40 of about 64,092 (179)

Movement and Space Use Patterns of the Beale's Eyed Turtle (Sacalia bealei) Suggest Sensitivity to Environmental Changes and Poaching 比氏眼斑龟 (Sacalia bealei) 的活动与空间利用模式揭示其对环境变化及盗猎的敏感性

open access: yesWildlife Letters, EarlyView.
Using radiotelemetry, we found that the movement and home range of the endangered Sacalia bealei varied significantly across reproductive classes and seasons, with males exhibiting greater movement than females during wet and mating seasons. The species exhibits strong aquatic dependence, favoring deep pools interspaced among riffle‐pool sequences ...
Wing Sing Chan   +3 more
wiley   +1 more source

核药厂衰变池废水及周边水样中14C的快速筛查法

open access: yesFushe yanjiu yu fushe gongyi xuebao
为快速筛查对象水体中14C的存在与否,并提供定量测量结果,采用液闪计数区域优化的方法,结合内标法确定猝灭效应下的计数效率,实现了样品中14C活度浓度的快速准确分析,探测下限为1.8 Bq/L。应用于某核药厂衰变池及周边环境水样中14C活度浓度的分析,其中3个样品活度浓度低于探测下限,其余样品活度浓度分布在38~1 332 Bq/L。自制活度浓度已知的样品验证了该方法的准确性,测量结果相对参考值最大偏差仅1.1%。
戈 立新, 韩 刚, 赵 超
doaj   +1 more source

The Ultrasonic Liquid Level Instrument Based on STC89C52 Single Chip Microcomputer [PDF]

open access: yes, 2016
在工业上,液位的测量被广泛应用于工业控制领域。对于某些比较恶劣的测量环境,不适宜由人直接测量液位的高低,这种情况下可采用水位仪来测量液位。超声波水位计是非接触型液位计,超声波水位计具有精度高、安装维护方便、适用范围广、价格便宜等优点而被广泛应用,提高了工业生产的智能化和安全性。 目前超声波水位仪的功能和价格,不同的厂家和不同的型号之间,相差较大。国内的产品相对比较便宜,但功能简单,精度不高。国外进口产品功能相对完善,精度较高,但价格不菲。对于一些中小型用户和企业来说,较难承受其价格,且维修不方便。因此 ...
庄鑫斌
core  

Relative Habitat Suitability of the Gray Fox (Urocyon cinereoargenteus) in the Central Great Plains 大平原中部灰狐 (Urocyon cinereoargenteus) 的生境相对适宜性

open access: yesWildlife Letters, EarlyView.
Although once abundant across its range, gray foxes (Urocyon cinereoargenteus) are purportedly declining. While range maps indicate that gray fox potentially occur throughout the central United States, contemporary distribution maps are needed. We developed a Habitat Suitability Model for six states, leveraging gray fox presence data in an ensemble ...
Daniel J. Benson   +4 more
wiley   +1 more source

Scaling from microsite to landscape to resolve litter decomposition dynamics in globally extensive drylands

open access: yesFunctional Ecology, EarlyView.
Read the free Plain Language Summary for this article on the Journal blog. Abstract Decomposition is the transformation of dead organic matter into its inorganic constituents. In most biomes, decomposition rates can be accurately predicted with simple mathematical models, but these models have long under‐predicted decomposition in globally extensive ...
Heather L. Throop   +8 more
wiley   +1 more source

The design and development for X-ray absorption spectrum measurement system [PDF]

open access: yes, 2016
组织光学是生物医学光子学的理论基础,组织光学特性参数的测量是其最重要也最艰难的任务,生物组织在不同生理状态下的成分会发生变化,健康与病变组织对光的吸收和散射不同,其光学参数也会随着光的波长而变化,测定组织在不同生理状态下的光学参数就可以对疾病进行诊断甚至前期诊断,进而及时进行治疗。制约组织光学发展的一个很重要的因素就是,所用光源(紫外到红外波段)对组织的穿透能力有限,无法实现较深部位的探测,而X射线具有良好的穿透能力,因此把组织光学推广到X射线范围不失为一种疾病诊断的有效途径 ...
胡波
core  

From pollen provision to pollinator: Species‐specific sterol assimilation by wild bees in urban landscapes

open access: yesFunctional Ecology, EarlyView.
Read the free Plain Language Summary for this article on the Journal blog. Abstract Human‐driven landscape change, particularly urbanization, is reshaping pollinator communities, yet the functional traits that mediate species persistence remain poorly understood. Dietary specialization is commonly used to predict species vulnerability.
Yan Yang   +5 more
wiley   +1 more source

Accuracy of diabetes screening methods used for people with tuberculosis, Indonesia, Peru, Romania, South Africa [PDF]

open access: yes, 2018
Objective To evaluate the performance of diagnostic tools for diabetes mellitus, including laboratory methods and clinical risk scores, in newly-diagnosed pulmonary tuberculosis patients from four middle-income countries.
Alisjhabana, B   +19 more
core   +2 more sources

Anthropogenic nitrogen addition interrupts seasonal connectivity and structures of plant–pollinator networks

open access: yesFunctional Ecology, EarlyView.
Read the free Plain Language Summary for this article on the Journal blog. Abstract Ecological communities are stressed by rapid and complex anthropogenic changes, threatening the persistence of biotic interactions and ecosystem functioning. Plant–pollinator communities, for instance, undergo structural transformations as a result of land‐use change ...
Erliang Gao   +8 more
wiley   +1 more source

基于量子级联激光器的ADN基液体发动机稳态燃烧CO特征浓度的实验测量 [PDF]

open access: yes, 2015
二硝酰胺铵(AND)作为一种绿色无毒推进剂已在固体推进剂以及液体推进剂领域得到一定程度的应用,是未来化学推进技术的一个新方向.目前我国正处于ADN基液体推进剂研究的起始阶段,对于其燃烧反应过程的研究是当前的一个研究重点.由于ADN基液体推进剂催化分解及燃烧反应过程复杂,相关的实验结果国内外公开文献发表较少,因此有必要开展ADN基液体发动机催化分解及燃烧反应的实验研究.本实验采用基于量子级联激光器的吸收光谱诊断技术,对ADN基液体发动机燃烧室内燃烧过程进行探究 ...
余西龙   +5 more
core  

Home - About - Disclaimer - Privacy