ADμ C845在配料控制器中的应用

本文从应用角度出发，介绍了ADμ C845的主要特点、功能及其使用要点。在此基础上，根据配料生产的工艺要求，以ADμ C845为核心，设计了一种新型配料控制器。详细介绍了仪表的硬件电路设计，给出了A／D转换部分C51源程序。该仪表具有自动称重、配料控制和联机通信等功能，实际使用运行稳定、效果良好。     

准噶尔盆地侏罗系储集层的基本特征及其主控因素分析

从描述储集层基本特征、分析储集层性质的主控因素、建立储集层成因模式和评价、预测储集层性质这 4个层次 ,研究准噶尔盆地重点勘探目标区的侏罗系储集层。系统总结侏罗系储集层岩石学特征 ,认为成岩压实作用强弱是控制储集层性质的关键因素 ;指出相对优质储集层均为剩余原生粒间孔隙型储集层 ,溶蚀作用对渗透率贡献小 ;非煤系储集层的孔隙保存条件明显比煤系储集层好 ,这是三工河组、头屯河组和吐谷鲁群的物性普遍优于八道湾组和西山窑组的原因。在确定储集层性质的控制因素和控制机理基础上 ,建立了煤系和非煤系两大类储集层的成因 演化模型。在上述研究的基础上 ,分地区、分层位评价了储集层 ,并预测了不同渗透率储集层的深度界线及相对优质储集层的平面分布。图 6参 10     

α-蒎烯催化加氢反应的研究

以FYX - 2G型高压搅拌釜为加氢反应器 ,测定了在不同搅拌器型式和搅拌转速下高压釜的持气量和反应效果 ,认识到α 蒎烯催化加氢是外扩散控制的反应 ,当搅拌转速为 6 0 0r/min时 ,基本上能消除外扩散的影响。考察了Raney镍和Pd/C催化剂、反应温度在 35 3～ 499K ,压力在 4 0～ 10MPa的条件下对α 蒎烯加氢转化率和选择性的影响 ,结果表明Raney镍更适宜于α 蒎烯催化加氢 ,其转化率随温度、压力增加而提高 ,但选择性下降。采用温度 35 3～ 433K、压力 4 0～ 7 0MPa的操作序列 ,克服了α 蒎烯加氢转化率与选择性互为逆向的缺点 ,缩短了反应时间 ,制得了顺反比高达 18 2∶1的蒎烷 ,并且发现加氢反应从温度 433K开始有副产物对烷生成 ,当温度超过 45 6K时 ,加氢过程还出现飞温现象。     

NBR/PP热塑性弹性体研究进展

阐述了NBR／PP共混热塑性弹性体动态硫化胶的国内外研究进展、微观相态结构、性能、应用及展望。     

中国陶瓷业如何与国际市场对接——访中国建筑卫生陶瓷协会秘书长缪斌

我国是陶瓷生产大国,近几年发展速度很快.2001年,我国的建筑陶瓷产量约20亿平方米,卫生瓷5000万件以上,全年全行业出口额超过2亿美元,创历史最好水平.加入WTO给我国陶瓷行业带来了很多机遇和挑战,但我们究竟与意大利、西班牙等陶瓷强国差距在哪里呢?记者最近走访了中国建筑陶瓷协会秘书长缪斌先生.恰逢秘书长刚从欧洲考察回来,便聊起这次欧洲之行……     

Accumulation of thiobarbituric acid‐reactive substances in cured pork sausages treated with propolis extracts

Propolis collected by bees has many components that possess antifungal, anticancer and antioxidant properties. Cured ground pork meat was treated separately with 0.4% w/w ethanol‐extracted propolis (EEP 0.4%), 0.6% w/w water‐extracted propolis (WEP 0.6%), 0.8% w/w dried residue of ethanol‐extracted propolis (DREEP 0.8%) and 0.1% w/w potassium sorbate (PS 0.1%) and made into sausages. Thiobarbituric acid‐reactive substances (TBARS) were measured in the sausages to assess the effects of storage at 5, 10 and 20 °C after 0, 2 and 4 weeks. After 4 weeks of storage at 5 °C the sausages treated with EEP 0.4%, DREEP 0.8%, WEP 0.6% and PS 0.1% yielded TBARS values which were 50, 59, 35 and 91% respectively of the control value. There was an increase of 0.33 mg MDA kg^?1, the lowest of all treatments, in TBARS for the 0.4% w/w EEP‐treated sausages. The curing process will control microbiological spoilage, as will potassium sorbate. © 2002 Society of Chemical Industry     

Natural quality two-band LPC coding of speech at 880 bit/s withframe interpolation

A novel frame interpolation technique for two-band linear predictive coding (LPC) vocoders is proposed for maintaining natural speech quality at bit rates below 1 kbit/s. Experimental results show that the speech quality of the proposed vocoder is quite natural at bit rates 880 bit/s and comparable to that of 4.8 kbit/s CELP     

Trace elements in particles of motor vehicle exhaust in Shanghai

A nuclear microprobe with high spatial resolution and high analytical sensitivity was applied to analyze trace elements,especially lead,in vehicle exhaust of Shanghai city.The result shows that the chemical composition and its corresponding x-ray relative intensity are different among different vehicle exhausts.There are many kinds of metal elements in particles of vehicle exhaust.most are harmful to people,such as Ti,Cr,Mn,Pb,etc.We found that the lead concentration was 6820μg/g and the bromine concentration was 5300μg/g in the exhaust from Santana using leaded gasoline(SULG).which is higher than any other kinds of vehicle exhausts.We have also detected the minimum lead in the particles of unleaded gasoline and its content varies from one to another.Its mean concentration was 450μg/g and the highest reached 6210μg/g.The unleaded gasoline‘s Pb existed in the whole particle while the leaded gasoline‘s enriched in the surface of the particle and was more harmful to the human beings.     

Effects of solidification structure on fatigue crack initiation and fatigue strength in Al−Si−Mg cast alloys

Rotating-bending uniaxial fatigue tests and micro-fatigue crack initiation tests were carried out using a permanent mold cast (PMC) and semi-solid die cast (SDC) with Al−7%Si−0.35%Mg composition in order to examine the relationship between solidification structures and fatigue behaviors. The crack length was measured using a replication method. Fatigue strength was improved in SDC, which was almost consistent with the predicted fatigue strength using the size of Si particle cluster. Resistance to fatigue crack initiation and fatigue strength were improved in SDC owing to the finer Si cluster and to higher ultimate tensile strength. Fatigue crack in PMC was preferentially initiated at pores. For SDC, the fatigue crack was initiated at the Si particle/matrix interface, and then sucessively grew along eutectic cell boundaries.     

河道治理工程水土保持设计

河道治理工程的实施会对工程区域内的自然生态环境和水土保持带来负面影响。以独流减河左堤治理工程为例 ,分析工程建设中可能造成的水土流失影响 ,从工程和生物两方面提出水土保持的防治措施 ,并对其投资进行了初步估算。