猪舍氨气排放预测模型的研究现状

该文就氨气对环境的影响和猪舍氨气排放机制进行了简要的叙述，详细综述了氨气排放的机理模型和基于不同因素建立的经验模型。从中可以看出，国外对氨气排放的模型做了大量的研究，也取得了一定的研究成果，但是不同的研究结果有一定的差异。最后针对我国的实际情况，对我国氨气排放需进一步研究的问题进行了探讨。     

小城镇住宅建设存在的问题及可持续发展对策

结合对中小城市小城镇住宅的调查研究,指出了现阶段小城镇住宅建设中存在的一些问题和现代小康家庭对住宅设计的影响及人们对设计的更高要求,提出了小城镇住宅可持续发展措施。     

考虑农村建筑安全性的居民点整理潜力界定及估算方法研究

目前推广运用的农村居民点整理潜力定义和测算方法不能测算危房改造潜力,无法满足当前农村居民点整理的要求。针对上述问题,该文首先从农村居民点和农村居民点整理的定义出发,运用推理分析法重新界定了农村居民点整理潜力;然后根据研究区居民点空心化成因,提出了基于居民点用地分类的整理潜力测算方法,居民点用地分为3级,一级依据用途分为5类,二级依据建筑设施安全性分为安全、不安全、无使用功能3类,三级依据利用状况分为使用、闲置、废弃3类;将不安全、无使用功能的二级用地和其他建设用地中的未利用地和边角地定义为整理潜力,并将用于居民点用地的潜力定义为改善生存条件潜力,其余潜力定义为土地利用扩展潜力,再根据整理的难度,将不安全使用类用地的潜力定义为难实现潜力,其余潜力定义为易实现潜力;最后运用该方法测算了下吐京村的居民点整理潜力。结果表明:该村有居民点整理潜力10.66 hm~2,改善生存条件潜力0.76 hm~2,土地利用扩展潜力9.90 hm~2,易实现潜力8.19 hm~2,难实现潜力2.47 hm~2。该文提出的农村居民点整理潜力定义和测算方法可以测算危房改造潜力,依据测算结果进行农村居民点整理,可实现农村危房改造和空心村整理。     

华北冬季密闭兔舍显热回收通风系统应用效果研究

针对华北地区常见围护结构的冬季不供暖密闭种兔舍保温与通风的矛盾问题,该文通过试验研究该类型兔舍不通风及运行显热回收通风系统(sensible heat recovery ventilation,SHRV)2种状态下的舍内空气质量、SHRV节能通风效果,并对比分析了SHRV结合均匀开孔送风和一端开口送风方式对舍内温度及气流分布的影响,探究SHRV在该兔舍的适用性。结果表明,相比于舍内不通风状态,运行SHRV时,舍内平均温度无显著波动;运行1 h后NH_3和CO_2浓度分别从9.9 mg/m~3和0.23%下降到4.2 mg/m~3和0.09%,湿度从84%下降到56%适宜水平,舍内空气质量改善明显。在该地区舍外温度-6～5℃时,SHRV可使新风温度平均提高3.4℃,平均显热回收效率和能效比(coefficient of performance,COP)分别为65%和5.1,达到了国家节能标准(60%和2.5)。比较分析风管一端开口送风与管道均匀开口送风发现,均匀开口送风可使舍内平均风速降低到0.2 m/s以下,减少舍内气流和温度分层,提高送风均匀性,降低动物冷应激。研究表明,在该地区常见围护结构不供暖密闭种兔舍使用SHRV可有效缓解通风与保温的矛盾,但若要达到更理想的节能通风效果,需采取适宜的芯体片间距,增加饲养密度、加强畜舍围护结构的密闭性提高保温效果。     

闽南人居环境的理水智慧初探

闽南地区依山靠海,处于江南与岭南的过渡地带,与台湾隔海相望。自唐以来,闽南人居环境既吸收了中原成熟的人居建设经验又在不断的对外交流中融汇了海洋文明,形成了独具特色的理水智慧。该地区的城镇、村落、风景名胜、私家园林及水利工程结合实用功能形成了江河湖海互为连通的完整水系,又结合自然、文化形成颇具诗情画意的人文景观。其理水手法大致分为借水、近水和聚水3种,以此获得水与环境、实用与艺术、自然与文化的完美统一,并形成了闽南地方特色。结合当今水资源的可持续发展背景下研究进展,探讨闽南人居环境的理水的当今启示。     

A questionnaire-based,retrospective field study of persistence of Salmonella Enteritidis and Salmonella Typhimurium in Danish broiler houses

A questionnaire-based, retrospective field study was conducted in 78 Danish broiler houses (analytical units) on 42 farms. In spring 1997, all these broiler houses had been infected with Salmonella Enteritidis, phage type 8, and/or Salmonella Typhimurium, definitive-type 66, by day-old chicks delivered from the same hatchery. Because these two salmonella types had not been detected in the Danish broiler sector before and the broiler houses were infected in a period of low salmonella prevalence, the study could focus on farm-related factors, without being distorted by other salmonella infections.

The same person visited all 78 broiler houses, and farm-related factors were listed both from personal observations and by interrogating the person in charge of attending to the broilers. Additional factors (noted at the visits) were recorded in a later telephone interview. Altogether, 187 variables were analyzed.

Broiler houses were divided into single-infection houses (which had one or both of the salmonella types in only one crop), and multiple-infection houses (where infection occurred in multiple crops). This was done both generally and separately for each of the salmonella types.

Factors associated with house status—but that were beyond the control of the farmer—were the salmonella type and the percentage of salmonella positive samples in the first crop. Factors which could be controlled by the farmer and which were associated with reduced prevalence of multiple-infection houses included antiseptic soap and water for washing hands in the anteroom, hygiene barriers when removing dead broilers, gravel alongside the broiler house, systematic checks of indoor rodent-bait depots, and combined surface and pulse-fogging disinfection.     

猪舍中氨的释放及其日粮调控

随着养猪业的发展,养猪生产过程中所带来的环境污染问题已日益受到人们的关注。严重的环境污染,特别是氨气和粪便的污染,不但对动物和人类的健康造成极大的威胁,而且导致环境酸化、土壤和地表水的污染。本文主要综述了减少养猪生产过程中氨的释放及其日粮调控方法,同时对氨产生的过程及其毒害也作了简单的介绍。     

住宅给排水设计

随着人民生活水平的提高,对居住环境及条件的要求也越来越高。特别是对厨房和卫生间的给排水设计要求更高。本文从卫生间、厨房设计中的设备选型、管道的隐蔽性、材质的选用更换和维修及美观等几方面进行阐述。     

城市住宅建设中土地供应问题的实证研究

本对城市住宅建设现状进行了实证研究，分析了城市土地管理存在的问题，并介绍了土地供应政策的调整。     

Research on the Evolution of Fire-sealing Gable Walls Diversity in Leizhou Traditional Vernacular Red Brick Dwellings

Leizhou vernacular red brick dwellings are a landmark symbol in Lingnan region which distinguishes them from vernacular dwellings in other places. Originating from Fulao traditional vernacular dwellings and inheriting their advantages, Leizhou traditional