The Impact of Metastable Intermolrecular Nanocomposite Particles on Kinetic Decomposition of Heterocyclic Nitramines Using Advanced Solid‐Phase Decomposition Models

Journal of Inorganic and Organometallic Polymers and Materials - Surface oxygen of oxide catalyst has low coordination number; they are negatively charged. Surface oxygen can act active site for...     

Rheology of natural fibers thermoplastic compounds: Flow length and fiber distribution

The presented study investigates the flow length and the corresponding fiber content distribution in the injection‐moulded natural fiber reinforced thermoplastics and its relation to fiber type and processing parameters such as injection pressure, temperature, injection rate and mould tempering by increasing die temperature. In this research, polypropylene compounds with nominally 30 wt % hemp and sisal fibers are investigated. The influence of the injection pressure (500 and 1000 bar), melt temperature (180°C, 200°C, and 220°C), and die temperature (23°C and 80°C) on the fiber content distribution all over the sample is investigated. An increasing linear trend of fiber content along the spiral length is observed as an evidence of a fiber/polymer multiflow system. A pattern for fiber content distribution with respect to the fiber length along the injected spiral can be distinguished, where the longer fibers are usually found at the end of the injected part and the shorter fibers remain near mould entrance point. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39861.     

Comparison of wound culture and bronchial lavage in the severely burned child: implications for antimicrobial therapy

BACKGROUND: The relationship of the burn wound flora to microbial pathogens in the tracheobronchial tree has important implications for antimicrobial therapy in the severely burned patient. Management of septic complications is bolstered by surveillance quantitative wound cultures (QWC) and bronchial lavage fluid (BLF) cultures. OBJECTIVES: To compare the organisms present in BLF with those found in QWC and to determine if QWC can predict BLF results. DESIGN: Results of BLF cultures from all patients who underwent bronchial lavage from January 1, 1996, to December 31, 1996, at our institution were compared with QWC data from the same date. Criteria for a positive match included an identical antibiotic susceptibility pattern and biotype. Match rates were calculated qualitatively and quantitatively. RESULTS: In 30 (48%) of the 62 BLF cultures, there was a match between the organism identified in the BLF and the QWC. When strict quantitative criteria were applied, the match rate was only 9 (14%) of 62. Burn size and inhalation injury had no significant effect on match rate. CONCLUSIONS: Whereas the microbial pathogens were similar in the QWC and BLF, linear regression showed no value of QWC in predicting BLF culture results. The difference between qualitative and quantitative match rates suggests cross-colonization between the burn wound and tracheobronchial tree, but little to no cross-infection. The QWC and BLF cultures must be performed independently in determining antimicrobial specificity in the burned patient.     

Cold Thermal Storage and Peak Load Reduction for Office Buildings in Saudi Arabia

This paper involves the investigations of the chilled water and ice cold thermal storage technologies along with the associated operating strategies for the air conditioning(AC) systems of the typical office buildings in Saudi Arabia, so as to reduce the electricity energy consumption during the peak load periods. In Saudi Arabia, the extensive use of AC for indoor cooling in offices composes a large proportion of the annual peak electricity demand. The very high temperatures over long summer periods, extending from May to October, and the low cost of energy are the key factors in the wide and extensive use of air conditioners in the kingdom. This intense cooling load adds up to the requirement increase in the capacity of power plants, which makes them under utilized during the off-peak periods. Thermal energy storage techniques are one of the effective demand-side energy management methods. Systems with cold storage shifts all or part of the electricity requirement from peak hours to off-peak hours to reduce demand charges and/or take advantage of off-peak rates. The investigations reveal that the cold thermal energy storage techniques are effective from both technical and economic perspectives in the reduction of energy consumption in the buildings during peak periods.     

Institutional disposition and management of end-of-life electronics

Institutions both public and private face a challenge to develop policies to manage purchase, use, and disposal of electronics. Environmental considerations play an increasing role in addition to traditional factors of cost, performance and security. Characterizing current disposition practices for end-of-life electronics is a key step in developing policies that prevent negative environmental and health impacts while maximizing potential for positive social and economic benefits though reuse. To provide a baseline, we develop the first characterization of quantity, value, disposition, and flows of end-of-life electronics at a major U.S. educational institution. Results of the empirical study indicate that most end-of-first-life electronics were resold through public auction to individuals and small companies who refurbish working equipment for resale or sell unusable products for reclamation of scrap metal. Desktop and laptop computers sold for refurbishing and resale averaged U.S. $20-100 per unit, with computers sold directly to individuals for reuse reaching $250-350 per unit. This detailed assessment was coupled with a benchmarking survey of end-of-life electronics management practices at other U.S. universities. Survey results indicate that while auctions are still commonplace, an increasing number of institutions are responding to environmental concerns by creating partnerships with local recycling and resale entities and mandating domestic recycling. We use the analyses of current disposition practices as input to discuss institutional strategies for managing electronics. One key issue is the tension between benefits of used equipment sales, in terms of income for the institution and increased reuse for society, and the environmental risks because of unknown downstream practices.     

Improved utilization of desiccant material in packed bed dehumidifier using composite particles

Solid desiccant dehumidifiers are widely used in drying processes. In most of these dehumidifiers, the desiccant material is used as packed bed of granule or spherical particles. Investigations of intra-particle heat and mass transfer processes has shown that the entire portion of the particle is not participating effectively during adsorption as well as desorption processes [Pesaran AA, Mills F. Moisture transport in silica gel packed beds-I. Theoretical study. International Journal of Heat and Mass Transfer 1987; 30: 1037–49]. This is because the diffusion rate is very small compared to that of convection. In the present work, a new desiccant composite particle, in which the unutilized portion of the spherical desiccant particle is replaced with an inert particle, is proposed. By replacing the conventional particles with composite particles for the same mass of desiccant material, the available area for heat and mass transfer increases and more amount of desiccant material is effectively utilized. Further, in order to ascertain the improvement in the performance of the desiccant bed using the composite particles, various factors like thermo-physical properties of the inert material, composite particle thickness ratio, bed configuration, bed volume, the pressure drop and the increase in total adsorbed or desorbed mass have to be considered. In view of this, a theoretical investigation of the operation of vertical solid desiccant packed bed dehumidifier, using both conventional silica gel particles as well as the new proposed composite silica gel particles has been reported. A modified solid side resistance (MSSR) model is developed for the prediction of intra-particle temperature and water content profiles. Results of the present theoretical models, when applied to packed bed of conventional silica gel particles, agree well with the experimental results from the literature for both desorption and adsorption processes. From the theoretical results, more utilization for the desiccant material is obtained when ordinary silica gel particles are replaced by composite silica gel particles. For the same amount of desiccant material and same mass flow rate of air, using particles of 0.2 thickness ratio the pressure drop decreases by about 60% for the case investigated. In addition, an increase of about 11.07% and 20.46% in total mass adsorbed and desorbed respectively are obtained. At the time when adsorption process ends, an increase of 15.5% in the bed effectiveness has been obtained. In addition, the expected improvement in total mass adsorbed and desorbed is observed to be dependent on the inert material thermo-physical properties for thickness ratio less than 0.5. An optimization technique relating the composite particle design, resulting savings in pressure drop and bed volume increase is proposed.     

Comparative assessment of pest management practices in potato production at Farmer Field Schools

Farmer field schools (FFS) and other participatory approaches are useful methods for rapid delivery of agricultural technologies, knowledge, and information in resource-constrained agro-ecosystems. Cultivar selection, weekly fungicide applications and integrated disease management (IDM) based on a disease monitoring strategy were evaluated at FFS for late blight control. Farmers’ knowledge and perceptions of pest management and agronomic practices were also assessed for both FFS participants and non-participants from 1999–2002. Late blight development and tuber yield varied among field schools, but cultivars had significant effects on late blight severity and yield over a range of disease management options relative to the untreated check. FFS participants and non-participants used diverse sources of pest management information, but differed significantly (P?<?0.05) in their use of management methods and practices. Cultivar resistance and fungicides were ranked as major components of pest control by 18%–85% and 7%–30% of FFS participants and non-participants, respectively. Differences in knowledge of cropping practices and pest biology, causal agents, disease symptoms, factors favoring disease development and cultural management of insects and storage pests were recorded. Participatory field experiments, access to resistant cultivars, disease management and use of various agronomic practices learnt at FFS can greatly improve pest control and potato production.     

Uterine myomata and outcome of assisted reproduction

BACKGROUND: Open lung biopsy (OLB) has long been considered the gold standard for the diagnosis of parenchymal lung disease. With recent advances in computed tomographic imaging and diagnostic techniques (eg, bronchoscopy), we thought it necessary to reevaluate the role of OLB in the management of patients with interstitial lung disease. METHODS: We carried out a retrospective analysis of 103 OLBs performed at Hadassah University Hospital, Jerusalem, and Carmel Medical Center, Haifa, between 1980 and 1994. Data gathered included demographic information, underlying condition, indications for biopsy, diagnosis before biopsy, final diagnosis, change in therapy, and mortality. "Benefit" was defined as a change in therapy resulting in survival. RESULTS: There were 45 immunocompetent patients (group 1), 39 immunocompromised patients (group 2), and 26 children (group 3), 7 of whom were included in group 2 for analysis. Overall, a diagnosis was reached after OLB in 85% of patients. An unexpected diagnosis was reached in 52%, and a change in therapy was instituted in 46%. The overall mortality rate was 20%. In group 1, the mortality rate was 13%, and "benefit" from OLB was reached in only 18%. In group 2, the mortality rate was 39%, and "benefit" was achieved in 46%, and in group 3, the mortality rate was 12% and "benefit", 50%. CONCLUSIONS: Open lung biopsy is an excellent diagnostic technique. In immunocompetent patients, the "benefit" is relatively low, as therapy (corticosteroids) is frequently used after biopsy. In immunocompromised patients, therapy changes substantially after OLB, but mortality is high. Therefore, OLB should be reserved for patients in whom the diagnosis is likely to lead to a change in therapy and in patients in whom the underlying condition has a reasonable prognosis according to the clinical impression by the attending physician.