载体及反应条件对Pt/BaKL沸石催化剂芳构化性能的影响

研究了γ-Al_2O_3或SiO_2载体,以及反应条件对Pt/BaKL沸石催化剂芳构化性能的影响。发现经过碱化或负载Sn的γ-Al_2O_3作为载体,能够较好地保持该催化剂在正己烷芳构化反应中的高活性和高选择性,并有益于改善Pt/BaKL沸石催化剂的抗硫性能。     

Production of phosphoric acid with low content of impurities

The present work is to study the possibility for controlled distribution of the impurities when they are decomposed by sulphuric acid to wet phosphoric acid and phosphogypsum, as well as generating technological conditions for production of clean wet phosphoric acid and its derivatives - phosphoric fertilizers, food phosphates and other phosphoric products.A coefficient of distribution D_A is introduced as a general criterion for elements dispersion. The study includes relationships between the weight ratio sulphuric acid/natural phosphate and D_A; the period of decomposition and D_A; the particle's size content of the natural phosphate and D_A. The obtained experimental data and relationships about the influence of the above discussed technological parameters on dispersion of more than 23 elements allow for control of that process in wet phosphoric acid and phosphogypsum by selecting specific technological conditions. Thus, depending on the requirements of acid's consumers and procedures for secondary processing of phosphogypsum to end-products, a selective decomposition of the natural phosphates to phosphoric acid and phosphogypsum can be carried out with content of the impurities in those products varying in narrow limits.     

以应力分析为基础的汽包封头强度计算

本文介绍应力分析设计法的原理，通过有限元计算得到汽包封头的温度场、应力场，并以应力分析为基础对汽包封头强度作了校核。     

认清形势 振奋精神全面完成化工“八五”计划的各项任务

总结回顾了１９９４年中国化学工业的改革及发展现状，提出了１９９５年化工生产建设的目标及在化工行业改革方面的四项试点工作，强调了编制“九五”计划的重要性。     

三峡地区生态环境治理保护对策

三峡地区是全国山地灾害频发的地区之一，而由于工业的发展，沿江域镇环境污染已对长江水质构成威胁，三峡建库后，随着库区水位的抬高，长江流速变缓，排污能力减弱，易在城镇岸段和回水区形成污染带，为此，建议持续实施农业综合开发工程，扩大自然保护区，治理水土流失，改善农业生态环境，加大“长江上游防护林工程”、“长江上游水土保持工程”、“中低产田改造工程”的投资比重和治理范围，对于山地灾害防治的重点为地质灾害严     

Chemical vapor deposition of aluminum for ulsi applications

Aluminum has been used widely as a conducting material in the fabrication of integrated circuits, and chemical vapor deposition process for Al has been actively investigated for the application in ultra large scale integration. In this review, various precursors, mainly alkyl aluminum and alane compounds, and reaction mechanisms of these precursors in Al CVI) are described. Epitaxial growth and selectivity of the deposition are also discussed. In addition to thermal reactions, plasma and photochemical reactions are also briefly described.     

饮用水氯化中氯仿形成的动力学模式

以黄腐酸（ＦＡ）为卤仿前驱物质，分别测定不同投氯量、ＴＯＣ水平、温度以及ｐＨ值对ＣＨＣｌ３形成速率的影响，确定出ＣＨＣｌ３形成的动力学模式。该模式可用于预测投氯后的管网水中ＣＨＣｌ３的形成量，以便采取必要措施保证饮用水符合国家规定ＣＨＣｌ３〈６０μｇ／Ｌ的标准。     

The role of forest and bioenergy strategies in the global carbon cycle

Forest and bioenergy strategies offer the prospect of reduced CO₂ emissions to the atmosphere. Such strategies can affect the net flux of carbon to the atmosphere through 4 mechanisms: storage of C in the biosphere; storage of C in forest products; use of biofuels to displace fossil-fuel use; use of wood products which often displaces other products that require more fossil fuel for their production. We use the mathematical model GORCAM (Graz/Oak Ridge Carbon Accounting Model) to examine these mechanisms for 16 land-use scenarios. Over long time intervals the amount of C stored in the biosphere and in forest products reaches a steady state and continuing mitigation of C emissions depends on the extent to which fossil fuel use is displaced by the use of bioenergy and wood products. The relative effectiveness of alternative forest and bioenergy strategies and their impact on net C emissions strongly depend, for example, on the productivity of the site, its current usage, and the efficiency with which the harvest is used. When growth rates are high and harvest is used efficiently, the dominant opportunity for net reduction in C emissions is seen to be fossil-fuel displacement. At the growth rates and efficiencies of harvest utilization adopted in many of our base scenarios, the net C balance at the end of 100 years is very similar whether trees are harvested and used for energy and traditional forest products, or reforestation and forest protection strategies are implemented. The C balance on a plantation system that provides a constant output of biomass products can look different than the balance of a single parcel of land.     

液相对流对固液界面稳定性的影响

以模型合金丁二腈－乙醇的强制性晶体生长为基础，利用自行研制的液相对流驱动装置，详细考查了液相自然对流及强迫对流作用下，模型合金平界面失稳的动态生长过程，证实了液相的流动加快了液相温度与浓度分布的均匀化，从而增强了液／固界面的稳定性。并且随流动速度的增加，界面稳定性提高。