全文获取类型
收费全文 | 209篇 |
免费 | 5篇 |
国内免费 | 1篇 |
专业分类
安全科学 | 20篇 |
废物处理 | 10篇 |
环保管理 | 38篇 |
综合类 | 42篇 |
基础理论 | 37篇 |
污染及防治 | 43篇 |
评价与监测 | 16篇 |
社会与环境 | 6篇 |
灾害及防治 | 3篇 |
出版年
2024年 | 1篇 |
2023年 | 3篇 |
2022年 | 5篇 |
2021年 | 7篇 |
2020年 | 5篇 |
2019年 | 7篇 |
2018年 | 7篇 |
2017年 | 9篇 |
2016年 | 13篇 |
2015年 | 6篇 |
2014年 | 14篇 |
2013年 | 24篇 |
2012年 | 17篇 |
2011年 | 20篇 |
2010年 | 13篇 |
2009年 | 11篇 |
2008年 | 7篇 |
2007年 | 5篇 |
2006年 | 6篇 |
2005年 | 9篇 |
2004年 | 4篇 |
2003年 | 7篇 |
2002年 | 2篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1998年 | 3篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1991年 | 1篇 |
排序方式: 共有215条查询结果,搜索用时 171 毫秒
51.
In theory, larger colonies of social insects should have greater colony organisation. While inter-specific comparative studies provide support for this idea, there is little direct intra-specific evidence. We investigated differences in task specialisation between large (>450 workers) and small (<80 workers) colonies of the ponerine ant Rhytidoponera metallica. Observations of individually marked young or old workers revealed greater task specialisation in large colonies. Age polyethism was detected in large but not small colonies. In large colonies, old workers spent significantly more time foraging than young workers did, while young workers spent more time caring for brood. In small colonies, young and old workers spent a similar amount of time foraging and caring for brood. This difference in task allocation patterns in large and small colonies was associated with a difference in contact rates between workers. Workers in small colonies have a lower contact rate between nestmates and a greater variability in time between contacts than workers from large colonies. 相似文献
52.
Empathy, a multidimensional construct comprised of cognitive, affective, and behavioral dimensions, has been advanced as a critical predictor of prosocial behavior and effectiveness in the workplace. However, despite organizational interest in empathy, there is a lack of consensus on what empathy is, how empathy should be measured, and how empathy research can meaningfully contribute to our understanding of organizational behavior. This paper aims to provide a roadmap for researchers and practitioners interested in empathy in the workplace. We first provide an updated overview of the state of the broader multidisciplinary literature on empathy. On the basis of this literature, we outline the three dimensions of empathy, discuss the distinctions between state/trait and observer/judged empathy, and compare empathy with related constructs. This integrated multidimensional conceptualization provides the basis for our critical review and recommendations. We review the organizational research on empathy (1983–2018), identifying critical issues with how empathy has been conceptualized, measured, and designed, and offer practical recommendations for the advancement of organizational research on empathy. We conclude by highlighting two fundamental questions: (a) is empathy associated with important outcomes of interest to organizations and employees, and (b) can empathy be changed, and if so, how? 相似文献
53.
Andrew A. Millward Melissa Torchia Andrew E. Laursen Lorne D. Rothman 《Environmental management》2014,53(6):1043-1057
Urban vegetation can mitigate increases in summer air temperature by reducing the solar gain received by buildings. To quantify the temperature-moderating influence of city trees and vine-covered buildings, a total of 13 pairs of temperature loggers were installed on the surfaces of eight buildings in downtown Toronto, Canada, for 6 months during the summer of 2008. One logger in each pair was shaded by vegetation while the other measured built surface temperature in full sunlight. We investigated the temperature-moderating benefits of solitary mature trees, clusters of trees, and perennial vines using a linear-mixed model and a multiple regression analysis of degree hour difference. We then assessed the temperature-moderating effect of leaf area, plant size and proximity to building, and plant location relative to solar path. During a period of high solar intensity, we measured an average temperature differential of 11.7 °C, with as many as 10–12 h of sustained cooler built surface temperatures. Vegetation on the west-facing aspect of built structures provided the greatest temperature moderation, with maximum benefit (peak temperature difference) occurring late in the afternoon. Large mature trees growing within 5 m of buildings showed the greatest ability to moderate built surface temperature, with those growing in clusters delivering limited additional benefit compared with isolated trees. Perennial vines proved as effective as trees at moderating rise in built surface temperature to the south and west sides of buildings, providing an attractive alternative to shade trees where soil volume and space are limited. 相似文献
54.
Melissa G. Meadows Nathan I. Morehouse Ronald L. Rutowski Jonathan M. Douglas Kevin J. McGraw 《Behavioral ecology and sociobiology》2011,65(6):1317-1327
Quantification of animal colors is important to a variety of fields of research, especially those dealing with visual communication
and sexual selection. Most animal colors are easily measured using well-established spectrophotometric techniques. However,
the unique characteristics of iridescent colors present particular challenges and opportunities to quantify novel color metrics.
Due to the fine-scale angle dependence of iridescent coloration, color metrics, such as hue and brightness, must be measured
using methods that allow for repeatable comparison across individuals (e.g., by carefully controlling and measuring viewing
geometry). Here, we explain how the optical characteristics of iridescent colors should be considered when developing measurement
techniques, describe the pitfalls of some commonly used techniques, and recommend improved methods and metrics (angular degree
of color change and breadth of reflectance) for quantifying iridescent color. In particular, most studies of iridescent birds
to date have used less than ideal procedures and have not provided repeatability estimates for their methods. For example,
we demonstrate here that measuring coloration from overlapping patches of iridescent feathers may be problematic, and we argue
against methods that do not carefully control viewing geometry. We recommend measuring iridescence at maximal reflectance
angles using an apparatus that allows for sample rotation, and we compare this technique to some other commonly used methods
using iridescent gorget and crown feathers from Anna’s hummingbirds (Calypte anna). Our apparatus allows for the quantification of angular color change, and we found that maximal reflectance measurements
using single feathers are highly repeatable both within feather samples and among samples within an individual. 相似文献
55.
Courtney Wilkes Melissa Graetz Lilian Downie Michael Bethune David Chong 《黑龙江环境通报》2023,43(10):1310-1319
Cleft lip and/or palate (CL/CP) is the most common congenital craniofacial anomaly and parents often ask, “how did this happen?” Patients and families may benefit from access to a multidisciplinary team (MDT) from prenatal diagnosis into early adulthood. Multiple factors can contribute to the development of a cleft. We discuss the epidemiology and risk factors that increase the likelihood of having a newborn with a cleft. The purpose of this article is to review the prenatal investigations involved in the diagnosis and workup of these patients in addition to postpartum treatment, prognostic factors, and counseling families regarding future recurrence risk. 相似文献
56.
57.
58.
59.
60.
Despite the demonstrated utility of the Australian River Assessment Scheme (AUSRIVAS) to provide national-scale information on the biological condition of rivers, there is no commensurate scheme that can provide standardised information on physical habitat. Existing habitat assessment methods are not suitable for implementation on a national scale, so we present a new habitat assessment protocol that incorporates favorable elements of existing methods. Habitat Predictive Modelling forms the basis for the protocol because it can predict the occurrence of local-scale features from large-scale data, uses the reference condition concept, can be modified to incorporate a range of biologically and geomorphologically relevant variables, and employs a rapid survey approach. However, the protocol has been augmented with geomorphological variables and incorporates principles of hierarchy and geomorphological river zonation. There are four sequential components to the implementation of the protocol: reference site selection, data collection, predictive model construction and assessment of test sites using the predictive models. Once implemented, the habitat assessment protocol will provide a standardised tool for the assessment of river habitat condition at a variety of governance levels. 相似文献