Experimental investigation of a cook-off temperature in a hot barrel

The experimental investigations of the effect of contact time/temperature on initiating the cook-off using 7.62 mm calibre cartridge cases （CC） were conducted previously. These cartridges were filled with commercial off-the-shelf （COTS） double based （DB） propellant （Bulls Eye） and were loaded in a hot chamber. The thermal explosion temperature is of great significance to both weapon designers and safety inspectors as it provides the operational limit and safe operating temperature. For CC under test, it was found that the cook-off temperatures of this propellant were encountered with the heat transfer profile of the simulated gun barrel between 151.4 ℃ and 153.4 ℃, with a reaction occurring in less than 300 s after the round was chambered. Usefully, each experiment was found to be consistent and repeatable.     

Characterization of four new Lactococcus lactis bacteriophages isolated from dahi whey

Four lytic phages of Lactococcus lactis ssp. diacetylactis isolated from indigenous dahi whey were examined for their stability, growth characteristics and morphology. All these phages were partially inactivated by CHCl₃ , remained stable at 40°C and were partially inactivated at pH 3. There was a marked difference among these phages with respect to latent period, rise period and burst size. All phages belonged to Bradley's group B.     

EARLY DETECTION OF CLOSTRIDIUM PERFRINGENS ENTEROTOXIN AND ITS RELATIONSHIP TO SENSORY QUALITY OF COOKED CHICKEN

Growth, sporulation, and enterotoxin formation by Clostridium perfringens NCTC 8239 were determined in chicken thigh meat incubated at 45°C for 1.5 h and 37°C for up to 12.5 h. With an inoculum of 10⁶ vegetative cells per g, the cell counts reached mean log ₁₀ 7.32/g after 6 h of incubation and remained in that range through 14 h. Heat-resistant spores (log₁₀ 2.48/g) were first detected at 4 h, and the number increased to log₁₀ 5.19/g at 14 h. Enterotoxin (0.19 μg/g) was first detected after 2 h of incubation (1.5 h at 45°C and 0.5 h at 37°C) in the absence of detectable sporulation, and the enterotoxin concentration increased to 0.76 μg/g after 14 h. Significant differences (p < 0.01) in the odor, color, and texture scores for inoculated versus uninoculated cooked chicken following 2 h incubation correlated with the production of enterotoxin and suggested that these parameters could be used as indices of chicken spoilage by C. perfringens.     

New approach to facility locations decisions

In a rapidly changing and complex environment, facility location decisions require careful evaluation; both quantitative and qualitative factors must be considered. Existing methods emphasize the quantitative aspects of such decisions. In this paper, we introduce a new method that provides a framework for a comprehensive analysis of both qualitative and quantitative factors in order to reach a logical and rational decision for choosing a site.     

INFLUENCE OF PROCESSING AND COOKING METHODOLOGIES FOR REDUCTION OF PHYTIC ACID CONTENT IN WHEAT (TRITICUM AESTIVUM) VARIETIES

The research was aimed to determine the effectiveness of different cooking and processing methods for reduction of phytic acid (PA) in wheat. Wheat is the staple food in Pakistan, supplying mainly energy, protein and minerals requirements in the average daily diet of rural and urban families. But compounds like PA depreciate its quality. In the first phase of the present study, seven wheat varieties viz. Inqilab‐91, Chakwal‐97, Margalla‐99, Wafaq‐2001, G.A‐2002, N.R‐231 and N.R‐234, most commonly grown all over Pakistan, were analyzed for PA without any treatment. PA was within the ranged of 1.503 (Inqalab‐91) and 1.223% (N.R‐234). In the second phase, different processing methods like soaking, germination and heat treatment were applied to check their effect on the reduction of PA. All treatments resulted in gradual decrease in PA contents. The soaking treatment was applied for 4, 8, 12 and 24 h. Maximum PA loss was observed in Margalla‐99 (25.1%) while minimum (22.5%) in Chakwal‐97 after 24‐h soaking. The germination treatment was applied for 24, 36 and 48 h. The highest loss of PA was observed in Margalla‐99 (40%) while the lowest (37%) in N.R‐231 after 48‐h germination. Similarly, heat treatment was also applied for 10, 30 and 60 min. Maximum PA loss was observed after 60‐min heating in Wafaq‐2001 (32%) while minimum (27.0%) in N.R‐23. Different processing methodologies can be applied for the reduction of PA. Each and every method has its own merits. If one method is beneficial for the reduction of PA content in a wheat variety, it does not necessarily mean that the same method is good for the other.     

基于多水文数据关联分析的雨水口异常诊断

为了定量探究排水系统的不确定性,基于监测水文数据提出雨水口堵塞程度的评估方法. 通过描述雨水口淹没入流状态下的物理模型,获得监测水文数据与雨水口堵塞面积的关联;计算每次独立积水事件下雨水口平均堵塞面积,作为雨水口堵塞程度评估指标;使用移动平均法对评估指标进行处理,能够直观分析出雨水口的堵塞程度. 将该方法应用于东部沿海城市研究区域,用雨水口清理记录进行验证. 结果表明,有83%研究点位的雨水口堵塞情况可以被很好地鉴别出来,其中诊断为堵塞并被清理的点位准确率为75%,诊断为堵塞但未被清理的点位准确率为89%. 预测失败的点位多由雨水口清理记录不全造成,雨水口侧支管堵塞疏通的延后性会对计算结果造成干扰.