电子鼻研究进展及在中国白酒检测的应用

基于传感器技术、信号处理技术和模式识别技术发展起来的电子鼻技术是过去二十年中发展最为迅速的气相分析和气体检测技术之一,它已逐渐在生物医学、环境监测、农业生产、食品检测等多个领域得到应用.电子鼻是利用对待测气体具有交叉敏感性的传感器阵列将待测气体中的混杂气味组分信息转化为与时间、成分、浓度或含量相关的可测物理信号组,利用信号采集系统输出含有待测气体特征信息的数字信号,通过模式识别系统分析数字信号得到待测气体综合气味信息和隐含特征,实现对待测气体快速、系统、准确的鉴别和分析.本文综述了电子鼻技术中的传感器技术和模式识别技术及在中国白酒品牌鉴定、风味识别、酒龄检测方面的最新研究进展;以聚合物石英压电传感器型电子鼻为例,阐明该电子鼻的技术方案及其在中国白酒检测中的应用;展望电子鼻未来研究方向.      

烷基黄原酸丙烯酯去味试验及工业生产研究

烷基黄原酸丙烯酯产品使用原始工艺生产时,生产过程、废水及产品均会产生刺激性气味,严重制约该产品的生产和销售.通过对该产品产生气味机理的研究和检测,及催化剂的筛选,确定KH1催化剂能够达到去味效果.进一步对KH1去味催化剂展开了小试、中试、工业试验研究,最终确定了工业生产条件为:加入方式为在原有生产设备的基础上,增加KH...     

冷轧轧制油的成分解析及异味改善

随着城市化进程的加快,原本处于郊县的钢铁企业逐步演变为"城市钢厂",冷轧产品生产过程中的轧制油(乳化液)异味问题也日益突出.实验对冷轧工序异味和轧制油成分的对应关系进行了分析,利用全二维气相色谱-飞行时间质谱(GC×GC-TOFMS)建立轧制油中与气味相关的基础油、油性剂、各类添加剂和其挥发组分的检测方法.基于分析结果...     

AH36钢两相区非平衡凝固路径的数值预测

应用多元合金两相区凝固显微偏析数学模型,对AH36钢在一定冷却条件下的非平衡凝固路径进行了数值计算,获得了相应的局部固相分数与局部温度之间的变化关系,为该钢种对应的连铸浇铸过程仿真及其它凝固过程仿真提供了必要而准确的耦合数据,具有重要的理论意义和广泛的适用性.     

溶液中Na+浓度对控制结晶制备碳酸镍钴的影响研究

通过控制结晶制备碳酸镍钴,考察了硫酸镍钴溶液中Na+浓度变化对溶液pH的影响,以及对碳酸镍钴产品物化指标的影响.研究表明:溶液中不同浓度的Na+将影响硫酸镍钴的pH值,在沉淀工艺条件保持不变的条件下,Na+浓度的升高将导致溶液pH的升高,在控制结晶过程中影响到过程pH的控制;同时随着溶液Na+浓度的升高将导致碳酸镍钴粒度细化和BET的降低,从而影响产品的性能;溶液Na+浓度的变化对碳酸镍钴Na、S杂质元素含量无明显影响.     

不同处理对甜柿贮藏效果的影响

[目的]研究不同处理对甜柿在低温贮藏下生理和品质变化的影响.[方法]以不作任何处理为对照,研究保鲜袋、乙烯吸收剂、赤霉素和魔芋葡甘聚糖涂膜结合使用对果实呼吸强度、果实软化速度、细胞膜透性和营养物质变化的影响.[结果]在(1.0±0.5)℃的温度条件下,使用聚乙烯塑料薄膜袋包装和魔芋葡甘聚糖涂膜保鲜甜柿,硬果期为60 d;赤霉素、乙烯吸收剂结合保鲜膜的简易气调贮藏方法保鲜甜柿,硬果期可达90 d.赤霉素与乙烯吸收剂可单独使用,也可配合使用.[结论]该研究为甜柿贮藏方法及采后商品化处理操作规程的建立提供了相应的理论依据.     

CSP热轧过程温度场模拟

综合考虑传热、变形及变形过程中的再结晶之间的相互影响，对C—Mn钢在CSP热连轧过程的温度场进行了计算机模拟。确定了各种工艺条件下的传热边界条件及其对应的换热系数关系式，计算出了轧件变形过程中温度变化和温度场分布。算例表明，模拟计算具有较好的精度，能为进一步模拟带钢轧后组织演变和性能预测分析提供计算基础。     

热轧槽钢轧后冷却过程模拟

利用有限元软件对热轧20#槽钢轧后冷却过程进行模拟,获得了轧后冷却过程温度场变化规律及典型部位的温度变化.通过实际测量值进行验证,模拟结果与实际冷却过程吻合较好.为研究槽钢轧后冷却规律提供了一种方法,对设置终轧温度及改善冷却条件提供了理论依据,进而有利于保证产品性能和减小冷却变形.对生产过程中轧制工艺制定、残余应力研究具有指导意义.     

应用CSP热轧卷生产的冷轧与镀锌产品常见缺陷分析

应用数据统计、离线检验以及扫描电镜缺陷分析等手段,对应用CSP线生产的热轧卷在冷轧与镀锌过程中出现的产品问题进行了分析,分析结果表明,应用CSP热轧卷进行冷轧与镀锌产品生产,不但受与炼钢、连铸、热轧各工序密切相关的热轧卷质量的影响,而且与冷轧与镀锌生产线本身工艺有重要关联.为提高最终产品质量,应做好生产过程中的检验和信息传递.     

生产过程中乳化液电导率和pH值变化情况分析

乳化液中一些离子含量的变化,对轧制后成品的储存、应用有一定的影响.乳化液中离子含量的变化可通过电导率、pH值的检测结果表现出来.通过条件试验证明了在轧机生产过程中影响乳化液电导率、pH值变化的因素.针对这些影响因素,在生产过程中可以相应加强控制,减小其不利影响,以延长产品保存期限.     

转炉炉壳热应力分析

根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。     

Concept of freedom of infection of animal flocks

Totally negative results of epidemiological investigation of random samples do not prove the absence of the infection as the pathogen may be restricted to only a few animals in the herd for a long time. The statement "absence of infection" is critical for such situations. The question is raised, whether the statement "absence of infection" should be generally avoided. Classification of herds and flocks according to the prevalence of the pathogen would be more valid for the implementation of control measures.     

显微维氏硬度测量不确定度评定

对显微维氏硬度测量不确定度进行评定，建立了不确定度计算的数学模型，确定了影响实验结果的各项因素，计算出了各因素的标准不确定度，得出结果的扩展不确定度，并给出最终测量结果的表达式。     

The effect of amount of possession of the trait of hostility on accuracy of perception of hostility in others.

Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparison of rates of infection of two methods of emergency ventricular drainage

The rates of infection of two methods of external ventricular drainage in use at Atkinson Morley's Hospital--namely, (a) percutaneous drainage with Rickham reservoirs and (b) tunnelled ventriculostomies--were compared in this retrospective review. Percutaneous drainage of CSF with Rickham reservoirs was associated with a 27% rate of infection as identified by positive microbiological cultures; tunnelled ventriculostomy catheters had a 10% infection rate. The difference in the infection rate between the two methods was statistically significant (P < 0.015). Other variables examined, including the age and sex of the patients and the reasons for ventricular drainage, were not associated with an increased rate of infection. Most infections from either method were caused by a coagulase negative staphylococcus. The average duration of ventricular drainage before identification of positive cultures was 5.7 days for Rickham reservoirs and 6.0 days for ventriculostomies.     

浅析《野草》的版画特征

鲁迅先生一生热爱美术作品,对版画中木刻兴趣尤甚.<野草>作为其"写心之作",亦呈现出一些与木刻版画一致的审美特征:一是具有木刻版画的色彩特征,多对比、多冷色,有阴郁的美感;二是具有木刻版画的力度特征,环境描写、人物刻画处处刀锋毕现,遒劲有力,有一种"力之美".     

四辊破碎机车刀架的改造

针对四辊破碎机车刀架车削中存在的几个问题,详细介绍了电动车刀架的结构和工作原理,建立主要设计参数的数学表达式,并进行适当的分析。改造后,这种电动车刀架运行平稳、可靠、方便、省力,取得了预期的效果。     

Rehabilitation of disorders of the breaking of voice

The adolescent's breaking of the voice is the result of the substitution of the chest voice (or heavy mechanism) for the head voice (or light mechanism). In cases of late breaking, the voice is abnormally high-pitched and feeble, often with a distorted timbre, while the larynx is normal and pubescent. Such people are generally not fully aware of their voices' real nature. Therapy classically resorts to laryngeal manipulations, of which a new technique is put forward. Another therapeutic approach is based, on the one hand, on critical listening compared with a control male voice, thus enabling the subject to become aware of his own voice, and, on the other hand, on high intensity work which helps passing from head to chest voice.