Assessing the effects of line capture and barotrauma relief procedures on post-release survival of key tropical reef fish species in Australia using recreational tagging clubs

Abstract  Common coral trout, Plectropomus leopardus Lacepède, crimson snapper, Lutjanus erythropterus Bloch, saddletail snapper, Lutjanus malabaricus (Bloch & Schneider), red emperor, Lutjanus sebae (Cuvier), redthroat emperor, Lethrinus miniatus (Schneider) and grass emperor, Lethrinus laticaudis Alleyne & Macleay, were tagged to determine the effects of barotrauma relief procedures (weighted shot-line release and venting using a hollow needle) and other factors on survival. Release condition was the most significant factor affecting the subsequent recapture rate of all species. Capture depth was significant in all species apart from L. malabaricus and L. miniatus , the general trend being reduced recapture probability with increasing capture depth. Recapture rates of fish hooked in either the lip or mouth were generally significantly higher than for those hooked in the throat or gut. Statistically significant benefit from treating fish for barotrauma was found in only L. malabaricus , but the lack of any negative effects of treating fish indicated that the practices of venting and shot-lining should not be discouraged by fisheries managers for these species.     

松木防蓝变和脱色处理技术的研究

解决松木蓝变问题已成为松材加工高档用材的基础和提高松材商品附加值的关键。通过探索性试验和正交试验以及(?)差的分析比较,得到防蓝变的优配方为:0.75％A1 0.50％A3 0.10％B。此配方在试验所观察的10周内防治效力达到了100％。同时,对松木蓝变色斑的脱除研究表明,在浓度5％的C药剂中加入D药剂,调节其溶液的pH值为10左右,加热到50-60℃对板材进行处理可有效脱除蓝变色斑。     

中亚天然气管道工艺细节设计

针对中亚天然气管道项目工艺设计中钢管低温脆性、管道水压试验、阀门压力等级和材质选择、放空立管防雨水功能4个代表性问题进行了分析。在低温时,通过采取保温措施、控制材料低温韧性或制定相应站场操作原则,避免管道出现低温脆性断裂;关于管道水压设计,设计方在提交给钢管厂家的技术条款中应增加现场强度试压的压力值和试压所维持时间的信息项,钢管厂家投标时应将工厂内的水试验压力指标列入标书中;在选择阀门压力等级和材质方面,采用标准磅级、特殊磅级、提高磅级或者中间额定4种方案,以解决阀门不满足设计压力和设计温度要求的问题;针对目前中亚项目放空立管防雨水存在的缺陷,提出了新的放空立管设计方案。     

缓释复合肥料在不同pH值紫色土中氨挥发特性（简报）

采用“通气法”室内培养试验,研究了非包膜缓释复合肥（SRF）施入不同pH值紫色土壤后的氨挥发损失状况和动力学特性。结果表明,土壤pH值对SRF氨挥发有极显著影响,随着土壤pH值升高,氨的挥发损失增加,以石灰性紫色土＞中性紫色土＞酸性紫色土。与大粒尿素（PUR）相比,SRF的氨挥发速率和损失量显著降低。在石灰性紫色土中SRF氨挥发分别减少14.2%和7.18%,中性紫色土中SRF氨挥发分别减少32.3%和24.1%,酸性紫色土中SRF氨挥发分别减少76.8%和10.7%。3种紫色土中,SRF的氨挥发动力学特性可用一级动力学方程、E1ovich方程和抛物线扩散方程定量描述,根据这些模型可在给定时间内预测SRF的氨挥发量。SRF能大大减少在不同pH值土壤中因施肥造成的氮肥损失,从而减轻对环境的污染。     

灌溉与非灌溉条件下黄淮冬麦区不同追氮时期农田土壤氨挥发损失研究

采用通气法研究了灌溉与非灌溉条件下黄淮冬麦区农田氨挥发损失.结果表明,非灌溉条件下,麦田追肥氮的氨挥发主要发生在施肥后的5～25d内,追氮时期由起身期(SE,GS30)推迟到拔节期(JT,GS32),追肥氮的氨挥发速率峰值增大且出现时间提前;继续推迟至孕穗期(BT,GS41),氨挥发速率峰值减小.SE、JT和BT三个追氮时期的氨挥发损失量分别占追肥氮的24.84％～25.32％、25.42％～25.50％和14.77％～16.62％.灌溉(60mm)条件,不论何时追氮,麦田追肥氮氨挥发速率均变化较小,氨挥发损失量在N 0.40～0.55 kg/hm2之间,仅占追肥氮的0.36％～0.49％.非灌溉条件,氨挥发速率与0-10 cm土层土壤铵态氮浓度呈极显著的正相关关系;灌溉条件,氨挥发速率与10-20 cm土壤浓度呈极显著的正相关关系.土壤温度和降水是影响氨挥发的重要因素.此外,氨挥发还与农田土壤表面的通气状况有关,多穗型小麦品种更有利于减少麦田氨挥发的损失.     

长输天然气管道冬季冻堵防治实例

中国石化榆济输气管道在试运行过程中,因发生水合物冻堵事故,西源祠阀室、石门阀室、杨家峪阀室压力变化异常,通过分析上下游管道的运行参数和统计管道工程遗留的裸管段,初步确定两处裸管段为线路冻堵点:1#冻堵点位于西源祠阀室和石门村阀室之间的爬坡段,2#冻堵点位于石门村阀室和杨家峪阀室之间的U形弯管段。根据现场实际,在采取应急处置措施的基础上,将加注醇类抑制剂、管道天然气放空、全线降压运行和加装电伴热4种方法结合使用,很快缓解了冻堵现象,确保了管输安全。     

The application of geotechnical engineering techniques for the prevention and control of pollution

Recent innovations in the fields of geotechnical engineering, geochemistry, materials technology, hydrogeology and fluid mechanics are now increasingly being applied for the prevention and control of pollution arising from contaminated ground and landfill sites. In the field of geotechnical engineering the design and specification of low-permeability slurries for slurry trench cut-off walls and diaphragm walls is now increasingly being used as technique for leachate and groundwater control. In addition, the use of high-density polyethylene (HDPE), geomembranes and gas venting systems are now commonly used for the control of landfill gas. This paper describes the application of some of the available techniques with respect to leachate, groundwater and landfill gas control. © 1997 John Wiley & Sons, Ltd.     

Clinical signs of barotrauma in golden perch,Macquaria ambigua (Richardson), and associated effects on post‐release mortality and health

This study assessed the effects of different retrieval depths (2, 10 or 20 m), surface intervals (none or 15 min) and release methods (untreated, vented or recompressed) on the incidence of external and internal clinical signs of barotrauma (ECSB and ICSB) and post‐release mortality in golden perch, Macquaria ambigua (Richardson). Fish were assessed for ECSB before and after surface intervals and either monitored for mortality over 3 days in two deep cages or killed for internal examination. When all fish were left untreated, short‐term mortality increased with retrieval depth from 0% and 4.2% among 2 and 10‐m fish, respectively, to 19.2% among 20‐m fish; while surface interval only affected the incidence of two ECSB (excess buoyancy and a prolapsed cloaca). Mortality was also greater among 20‐m fish that were subjected to a 15‐min surface interval and left untreated (22.2%) or vented (22.2%) than those that were recompressed (5.6%). Of the ECSB, only exophthalmia was associated with increased mortality, with half of the affected fish dying. However, many fish retrieved from 10 and 20 m also sustained numerous ICSB, including compressed gonads or vital organs and ruptured or collapsed, haemorrhaging swimbladders that remained deflated for up to 3 days after release.     

含有非水相液体(苯)的土壤气相抽提体系传质实验研究

选取砂土作为实验室一维土柱通风实验的研究对象,考察了不同含水量(0%、21.9%、36.6%及51.2%)条件下,苯在气-水-油-固4相共存的土壤气相抽提体系(Soil vapor extraction,SVE)体系中的相间传质过程。并用局部相平衡模型及非平衡动力学模型预测结果与实验结果进行了比较。干燥情况下,局部相平衡模型可以描述通风过程,随着含水量的增加实验结果严重偏离平衡模型。含水量为21.9%、36.6%及51.2%时,非平衡动力学模型与实验结果较为符合。结果表明,土壤含水量影响气-液(Non-aqueousphase liquid,NAPL)间的传质,干燥土壤中相平衡模型可以描述SVE修复过程。随含水量的增加修复进程偏离相平衡模型较严重,此时需要用非平衡动力学模型来描述。     

Smoke Management Systems for Large Volume Space

Atria and other large volume space do not have the compartmentation that has traditionally been a major contributor of fire protection.The effectiveness of sprinklers in these large volume spaces is limited. For these reasons, smoke management systems for large volume spaces is of particular importance. Their primary goal is to maintain an enviroment in which the impact of smoke and heat on occupants is not life threatening. This involves keeping the height of the smoke layer above the highest level of occupancy for a defined period of time, longer than the expected time to evacuate the building. Three approaches to these systems are smoke filling , gravity smoke venting ,and smoke exhaust .This paper describes the design approaches to smoke management to achieve fire safety in atrium.