BiOCl催化剂的丙烷氧化脱氢催化性能

以_L-赖氨酸为模板剂,采用沉淀法制备了BiOCl催化剂,对催化剂进行了X射线衍射、N₂吸附-脱附和H₂-TPR等表征,并测试了BiOCl催化剂对丙烷氧化脱氢制丙烯反应的催化性能。结果表明,制备的BiOCl催化剂为四面体结构,500 ℃焙烧3 h后,催化剂比表面积为11.2 m²·g^-1,未完全还原氧物种的含量较多。随着反应温度升高,丙烷转化率和丙烯选择性增加,丙烷转化率为20%时,丙烯选择性达64.5%。     

An experimental study of solid timber external wall performance under simulated bushfire attack

With the increasing threat of climate change there is a need to use renewable and green materials such as timber for house constructions. Timber is not generally regarded as a suitable material for the construction of homes in bushfire (or wildland fire) prone areas. However, our understanding of the performance of solid timber wall constructions under bushfire conditions is still limited. The objective of this research was to conduct a pilot experimental study of a solid timber wall system to assess its performance under severe bushfire attack conditions typical in Australia's bush land. Eight log wall specimens with and without various protection coatings were exposed to thermal radiation field produced by a gas-fired radiation panel at the BRL A40 level in accordance with the relevant Australian test standard. The heat flux on the exposed surface and temperatures on both the exposed and unexposed surfaces were measured. Flaming combustion and self-extinguishment were observed on most of the specimens while the external radiant heat varied from 40 kW/m² to 16 kW/m². The charring depth of the log walls was also measured. The performance of the solid timber walls was evaluated against the relevant standard. The experimental work showed that solid log wall assemblies are resistant to severe bushfire threat and timber can be a suitable material for building in bushfire prone areas if sufficiently thick and well sealed.     

Population modelling in drug development

In this paper we discuss the vital role that population (hierarchical) modelling can play within the drug development process. Specifically, population pharmacokinetic/pharmacodynamic models can provide reliable predictions of an individualized dose-exposure-response relationship. A predictive model of this kind can be used to simulate and hence design clinical trials, find initial dosage regimens satisfying an optimality criterion on the population distribution of responses, and individualized regimens satisfying such a criterion conditional on individual features, such as sex, age, etc. Throughout we emphasize prediction and advocate mechanistic as opposed to empirical modelling, and argue that the Bayesian approach is particularly natural in this setting.     

Drinking water denitrification using a membrane bioreactor

A membrane bioreactor (MBR) was investigated for denitrification of nitrate (NO3(-)) contaminated drinking water. In the MBR, NO3(-) contaminated water flows through the lumen of tubular microporous membranes and NO3(-) diffuses through the membrane pores. Denitrification takes place on the shell side of the membranes, creating a driving force for mass transfer. The microporous membranes provide a high NO3(-) permeability, while separating the treated water from the microbial process, reducing carryover of organic carbon and sloughed biomass to the product water. Specific objectives of this research were to develop a model for NO3(-) mass transfer in the MBR, investigate the effect of shell and lumen velocity on NO3(-) mass transfer and investigate the effects of NO3(-) and organic carbon loading on denitrification rate and product water quality. A mathematical model of NO3(-) mass transfer was developed, which fit abiotic mass transfer data well. Correlations of dimensionless parameters were found to underestimate the overall NO3(-) mass transfer coefficient by 30-45%. The MBR achieved over 99% NO3(-) removal at an influent concentration of 200 mg NO3(-)-NL(-1). The average NO3- flux to the biomass was 6.1g NO3(-)-Nm(-2)d(-1). Low effluent turbidity was achieved; however, approximately 8% of the added methanol partitioned into the product water.     

Rural America: Unique opportunities for health care delivery and health services research.

A general deterioration is occurring in the quality of life of rural Americans, and it is affecting the quality of health and mental health service delivery. About 24% of the U.S. population lives in nonmetropolitan areas where the citizens are older, less well educated, have lower incomes, and are more homogeneous in terms of ace and ethnicity. Medicare and private insurance discriminate against rural services in their reimbursement policies, and there is a shortage of health personnel in rural areas. However, there has been renewed congressional action to meet rural needs. Both the House and Senate have established rural caucuses, and an Office of Rural Health Policy has been established in the federal executive branch. Legislative successes were achieved between 1985 and 1988. Rural initiatives will provide psychology with unique opportunities in the next several years. (PsycINFO Database Record (c) 2010 APA, all rights reserved)