Potential thread-level-parallelism exploration with superblock reordering

The growing number of processing cores in a single CPU is demanding more parallelism from sequential programs. But in the past decades few work has succeeded in automatically exploiting enough parallelism, which casts a shadow over the many-core architecture and the automatic parallelization research. However, actually few work was tried to understand the nature, or amount, of the potentially available parallelism in programs. In this paper we will analyze at runtime the dynamic data dependencies among superblocks of sequential programs. We designed a meta re-arrange buffer to measure and exploit the available parallelism, with which the superblocks are dynamically analyzed, reordered and dispatched to run in parallel on an ideal many-core processor, while the data dependencies and program correctness are still maintained. In our experiments, we observed that with the superblock reordering, the potential speedup ranged from 1.08 to 89.60. The results showed that the potential parallelism of normal programs was still far from fully exploited by existing technologies. This observation makes the automatic parallelization a promising research direction for many-core architectures.     

基于亲水/憎水复合膜的全热交换器换热换湿性能[

膜全热交换器由于可以同时回收空调排风中的潜热和显热而受到重视。研究了基于PVAL/PVDF复合透湿膜的全热交换器的透热透湿性能，实验测定了新风与排风之间的显热交换能力和水蒸气交换能力，并建立了基于亲水/憎水复合膜的逆流膜全热交换器传热传质计算模型，实验与理论结果吻合较好。结果表明，该复合膜全热交换器的总传热系数为20～35 W·m-2·℃-1，总传质系数为（1.5～3.5）×10-3 m·s-1。     

固体颗粒对三相气升式环流反应器流动特性的影响

将液相视为连续相,气相和固相视为分散相,同时考虑各相之间的相互作用,结合气液固三相流体的动力学理论,建立气液固三相环流反应器三流体湍流流动的Eulerian模型.采用计算模拟软件Fluent对三相环流反应器的流动状况进行模拟,考察表观气速、固含率、颗粒大小对反应器的气含率以及液体流动速度的影响.模拟结果较好地解释了气升式环流反应器内的三相流体行为,模型与实验结果较好地吻合,表明了模型的可行性.     

Effects of sulfate-reducing bacteria on the corrosion behavior of carbon steel

The influences of the growing process of sulfate-reducing bacteria (SRB) in seawater system on the medium state and corrosion behavior of carbon steel were studied by detecting solution state parameters and using corrosion electrochemical methods. The growing process of SRB in the seawater shows the three stages of growing, death and residual phases. The solution state parameters of the concentration of sulfide, the pH value and the redox potential changed during the three stages of the SRB growing process. And the corrosion rate of D36 carbon steel was accelerated during the growing phase and stable during the death and residual phases. The results indicate that the medium state and the corrosion rate of the steel do not depend on the number of active SRB, but depend on the accumulation of the metabolism products of SRB.     

Dietary fatty acids regulate cholesterol induction of liver CYP7α1 expression and bile acid production

In the present study we investigated the effects of dietary fats containing predominantly PUFA, monounsaturated FA (MUFA), or saturated FA (SFA) on lipid profile and liver cholesterol 7α-hydroxylase (CYP7α1) mRNA expression and bile acid production in C57BL/6J mice. The animals (n=75) were randomly divided into five groups and fed a basic chow diet (AIN-93G) (BC diet), a chow diet with 1g/100g of cholesterol (Chol diet), a chow diet with 1g/100g of cholesterol and 14g/100g of safflower oil (Chol+PUFA diet), a chow diet with 1g/100g of cholesterol and olive oil (Chol+MUFA diet), or a chow diet with 1g/100g of cholesterol and myristic acid (Chol+SFA diet) for 6 wk. The results showed that the Chol+SFA diet decreased CYP7α1 gene expression and bile acid pool size, resulting in increased blood and liver cholesterol levels. Addition of PUFA and MUFA to a 1% cholesterol diet increased the bile acid pool production or bile acid excretion and simultaneously decreased liver cholesterol accumulation despite decreased CYP7α1 mRNA expression. The results indicate that the decreased bile acid pool size induced by the SFA diet is related to inhibition of the liver CYP7α1 gene expression, but an increased bile acid pool size and improved cholesterol homeostasis are disassociated from the liver CYP7α1 gene expression.     

农药残留物的研究现状

从农药残留物的标准和检测方法等几方面介绍了农药残留物的研究现状。     

洗涤剂中磷酸盐与水质保护的研究与建议(续前)--国外禁限磷发展现状及有关建议

1 3 2日本禁、限磷效果1 3 2 1日本琵琶湖历年总磷浓度调查情况(见图1) :对以上结果有下列不同看法 :(1)禁磷收到了较好的效果 ,日本第一大湖泊—琵琶湖北湖近20年来 ,总磷浓度一直控制在水质标准以下(即0 01mg/L以下) ,琵琶湖南湖总磷浓度虽高于水质标准 ,但比实施“禁磷”措施的初期(1978年～1980年) ,湖水总磷浓度亦有明显程度的下降 ,以后一直稳定地维持在略高于水质标准的水平(0 021mg/L～0 024mg/L)。(2)禁磷没有效果 ,1984年日本无磷洗涤粉已占80 % ,1988年以后一直都保持在97 %以上 ,基本实现了无磷化 ,但水质并未随限禁磷的实施…     

聚丙烯交联技术发展现状

交联聚丙烯具有优异的机械性能和热性能。本文就当前聚丙烯的几种交联技术进行了总结与分类,并介绍了各自的反应机理。着重讨论了最常见的几种PP的交联工艺及其特性,包括有机过氧化物交联、硅烷接枝交联、辐射交联等。     

岩体结构面对大跨度隧道工程稳定性影响初步研究

基于对沈阳至大连（简称沈大）高速公路扩建工程韩家岭隧道区域调查和分析，研究了岩体结构面对隧道施工过程的影响，围岩失稳方式及可能遇到的问题，并提出了解决这些问题的措施。     

二-(4-羟基丁基)四甲基二硅氧烷的合成研究

采用一步法以二甲基二氯硅烷、四氢呋喃和金属镁粉为原料,在碘乙烷和单质碘催化下合成二-(4-羟基丁基)四甲基二硅氧烷。产物温合物减压过滤,以除去镁盐。滤液无需蒸馏提纯,而直接水解,干燥,减压蒸馏,收集71℃/1333Pa馏份。还探讨和优化合成条件:四氢呋喃与二甲基二氯硅烷之摩尔比应大于3.5;Grignard反应停止后应继续加热回流1小时;蒸馏时系统压力为1333Pa。