多年施用生物炭对河南烤烟种植区土壤呼吸的影响

为探究生物炭施用对土壤呼吸的影响,采用5 a定位试验(2013～2017年)研究了不施生物炭(CK)、施用1. 5 t·hm-2生物炭(T1)、施用15 t·hm-2生物炭(T2)、施用45 t·hm-2生物炭(T3)这4种处理下土壤呼吸及土壤水热因子的动态变化规律.结果表明:(1)在土壤中连续5a施入中剂量生物炭(T2:15 t·hm-2)显著降低了烤烟生长季土壤呼吸速率,降幅为25. 89%;当施入量增至45 t·hm-2(T3)时土壤呼吸速率显著增加,增幅为21. 48%(P 0. 05).(2)长期中剂量生物炭的添加显著降低了土壤异养呼吸速率和自养呼吸速率,降幅分别为29. 80%和28. 75%;大剂量生物炭(T3:45 t·hm-2)的施入显著增加了土壤异养呼吸速率,增幅为28. 88%.低剂量生物炭(T1:1. 5 t·hm-2)和中剂量生物炭均显著增加土壤呼吸中自养呼吸的比例,大剂量生物炭的施入显著增加了异养呼吸的比例(P 0. 05).(3)低剂量生物炭显著降低了烤烟生长季土壤5 cm温度;大剂量生物炭显著降低了土壤5 cm湿度.土壤呼吸与土壤5 cm温度之间呈显著指数相关,与土壤5 cm湿度之间未表现出显著相关(P 0. 05).综上,连续5a低剂量生物炭的施用对土壤呼吸无影响,适量生物炭的施用具有固碳减排效应,大剂量生物炭施用则会适得其反,建议生物炭施用范围应控制在15 t·hm-2以内.     

电子类备件贮存失效模式及测试方法研究

结合工程装备维修器材保障工作的实际情况,对扫雷车电子类备件贮存失效模式及影响因素进行了定性分析,提出了电子类备件技术性能测试方案,研究设计了相应的检测平台及适配器,对工程装备维修器材贮存质量管理及控制进行了初步探索。     

Interpretation of black sea sediments analytical data by the clustering approach

Analytical data consisting of chemical concentration of 11 inorganic components in 20 sampling stations from sediments collected from south‐western part of the Black Sea are treated by cluster analysis. The clustering reflects quite satisfactorily the relations between sampling zones and between chemical elements revealing new chemical and geochemical information.     

中小企业CAPP工具系统的研究与开发

针对中小企业的生产类型 ,分析了中小企业CAPP系统应具备的特点 ,并在此基础上 ,开发了一个基于特征和资源定制的CAPP系统 ,该系统集工艺设计和工艺管理于一体 ,从而较好地满足企业对CAPP的需求     

乌鳢仔鱼生化成分变化与其行为的关系

研究了１～１６ｄ龄乌鳢仔鱼水分、Ｎａ＋、Ｋ＋、脂肪和蛋白质含量的变化及其主要摄食行为．结果表明，初孵仔鱼含水量为５０．１５％～５２．４０％，并随发育进展持续上升到８６．３５％～８６．８６％，而仔鱼干重则在第６ｄ最低．Ｎａ＋、Ｋ＋在仔鱼前期波动较大，第８ｄ后稳步上升，脂肪食量在孵出后的前４ｄ基本上保持不变，第５ｄ下降１５．８５％，第６ｄ下降３４．３８％，此后一直下降．蛋白质含量前８ｄ变化很小，第８ｄ后开始大幅上升．结合行为学观察认为，油球在仔鱼前期主要作为“浮力器官”（ｂｕｏｙａｎｃｙｏｒｇａｎ），在后期则可补偿摄入能量的不足．     

碱渣的氧化脱臭处理及回用

介绍我厂新建碱渣氧化脱臭装置工艺特点、运行情况及脱臭后常汽碱渣的回用情况。实践证明，此装置对常汽碱渣脱臭效果好，脱臭后碱渣完全无臭；脱臭后碱渣回用于精制油口，油品质量合格，对下游环烷酸装置的环烷酸质量亦无影响。     

Solid components and acid buffering capacity of soils in South China

ＳｏｌｉｄｃｏｍｐｏｎｅｎｔｓａｎｄａｃｉｄｂｕｆｅｒｉｎｇｃａｐａｃｉｔｙｏｆｓｏｉｌｓｉｎＳｏｕｔｈＣｈｉｎａＱｉｕＲｏｎｇｌｉａｎｇ，ＷｕＱｉｎｇ，ＺｈａｎｇＹｕｎｎｉＤｅｐａｒｔｍｅｎｔｏｆＥｎｖｉｒｏｎｍｅｎｔａｌＳｃｉｅｎｃｅ，Ｚｈｏ...     

4m压力管离心铸造机液压传动

此文在介绍4m压力管离心铸造工艺对液压传动工作要求的基础上,重点介绍了液压传动的工作原理、组成及其主要特点.     

Coercive pressure as a moderator of organizational structure and risk management: Empirical evidence from Malaysian construction industry

Introduction: The construction industry in Malaysia has been bedevilled by myriads of risk issues that have hampered its smooth operations in recent times. This paper is an empirical assessment that aims to examine the effect of coercive pressure on the relationship between organizational structure and construction risk management among construction industry in Malaysia. Method: Based on the proposed model, a quantitative method was employed to obtain data from G7 construction industry operating within the peninsular Malaysia. Out of the 180 copies of questionnaire, 165 copies were properly filled, returned, and used for the analysis. PLS-SEM was used to analyze the obtained data. Results: The findings of the study affirmed that specialization, centralization, and management of risk by the construction industry had positive correlation. Conclusions: As anticipated, coercive pressure had positive moderating correlation with both formalization and the management of risk by the construction industry. Similarly, it was also found that in the course of carrying out construction activities, coercive pressure made significant interactive influence on formalization, specialization, and centralization. Practical Applications: Coercive pressure reduced the frequency of accidents among workers in the process of carrying out construction works.     

Developing a CFD heat transfer model for applying high expansion foam in an LNG spill

Liquefied natural gas (LNG) is widely used to cost-effectively store and transport natural gas. However, a spill of LNG can create a vapor cloud, which can potentially cause fire and explosion. High expansion (HEX) foam is recommended by the NFPA 11 to mitigate the vapor hazard and control LNG pool fire. In this study, the parameters that affect HEX foam performance were examined using lab-scale testing of foam temperature profile and computational fluid dynamics (CFD) modeling of heat transfer in vapor channels. A heat transfer model using ANSYS Fluent® was developed to estimate the minimum HEX foam height that allows the vapors from LNG spillage to disperse rapidly. We also performed a sensitivity analysis on the effect of the vaporization rate, the diameter of the vapor channel, and the heat transfer coefficient on the required minimum height of the HEX foam. It can be observed that at least 1.2 m of HEX foam in height are needed to achieve risk mitigation in a typical situation. The simulation results can be used not only for understanding the heat transfer mechanisms when applying HEX foam but also for suggesting to the LNG facility operator how much HEX foam they need for effective risk mitigation under different conditions.