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101.
鞠舰波 《中国特种设备安全》2022,(1)
本文以某炼油厂常减压塔顶冷凝冷却系统为研究对象,对该系统发生腐蚀泄漏进行原因分析。通过分析其腐蚀原因,提出了控制腐蚀的措施和方法,从而达到设备长周期运转的目的。 相似文献
102.
Summary. Tannins are plant defense compounds that exhibit antibiotic (e.g. toxic) and antixenotic (e.g. repellent) effects against
an array of plant pests. They are broadly divided into two major groups, hydrolysable tannins (gallotannins and ellagitannins)
and proanthocyanidins, each with an undetermined number of compounds. We investigated constitutive levels of hydrolysable
tannins and proanthocyanidins in the leaves and stems of American (Castanea dentata Marshall) (Fagales: Fagaceae) and Chinese (C. mollissima Blume) chestnut. American chestnut contained more proanthocyanidins in leaves and stems than Chinese chestnut, but Chinese
chestnut contained more foliar hydrolysable tannins. Regardless of these differences, gypsy moth (Lymantria dispar L, Lepidoptera: Lymantriidae) performance did not differ when fed American and Chinese chestnuts. We also investigated the
effects of jasmonic acid (JA) treatment on differential tannin induction in American and Chinese chestnut leaves and stems.
JA treatment increased proanthocyanidins in American chestnut stems and hydrolysable tannins in both tissue types of American
chestnut, but did not influence tannin concentrations in Chinese chestnut leaves or stems. HPLC-ESI-MS analysis of pooled
samples suggested that hydrolysable tannins in each tissue were qualitatively comprised primarily of ellagitannins, and JA
generally increased the number of hydrolysable tannins that could be detected by ESI-MS. Third, we investigated the performance
of gypsy moths on JA treated and untreated American and Chinese chestnut. Caterpillar relative growth was not influenced by
JA treatment on Chinese chestnut, but decreased in response to JA application on American chestnut. Our results indicate that
JA-dependent defenses differ between these chestnut species. This study improves our understanding of ecologically important
differences in tannin induction and herbivore susceptibility in Castanea, and has important implications in efforts for American chestnut restoration and commercial chestnut production. 相似文献
103.
105.
Gary D. Lynne 《Journal of the American Water Resources Association》1988,24(1):95-101
ABSTRACT: Economic information for efficient water allocation is difficult and costly to acquire under administrative water systems evolving under the Model Water Code. One approach to obtaining more information is to use a simulator like the Florida AGWATER model. The advantage of AGWATER is the potential for realistic prediction, because it operates at the field and day levels, using detailed information for each crop and tract. Unfortunately, such simulators are complex and require large amounts of costly input data. A better solution to the information problem may be to use markets for the marketable goods associated with water, because information is inherent in such a process. This approach will allow limited modeling and management resources to be put into using water models to generate information for the goods dependent on water that are difficult to market, like wildlife services. 相似文献
106.
107.
再制造工程是一种末端产品的资源化利用方式。阐述了再制造工程的内涵、在全生命周期中的地位及国内外发展现状,分析了再制造所能够带来的巨大的资源效益、经济效益、社会效益和环境效益,得出结论:再制造工程是末端产品进行资源化处理的最佳利用方式。 相似文献
108.
An activated semi-coke with industrial-scale size was prepared by high-pressure hydrothermal chemistry activation, HNO3 oxidation and calcination activation in proper order from Inner Mongolia Zhalainuoer semi-coke, which is rich in resource and cheap in sale.SO2 adsorption capacity on this activated semi-coke was assessed in the fixed bed in the temperature range of 60-170℃, space velocity range of 500-1300 h^-1, SO2 concentration of 1000-3000 ppmv, and N2 as balance. The surface area, elemental and proximate analysis for both raw semi-coke and activated semi-cokes were measured. The experimental results showed that the activated semi-coke has a high adsorption capacity for sulfur dioxide than the untreated semi-coke. This may be the result of increase of surface area on activated semi-coke and surface oxygen functional groups with basicity characteristics. Comparison to result of FTIR, it is known that group of-C-O-C-may be active center of SO2 catalytic adsorption on activated semi-coke. 相似文献
109.
A complex chromosome rearrangement, apparently a balanced translocation involving chromosomes 4,6, 15 and 16, was found in cultured cells of amniotic fluid from a 32–year-old primigravida who requested amniocentesis for prenatal diagnosis because of a family history of mental retardation. Chromosome analysis of peripheral blood from both parents were normal. The couple was counselled for the prenatal diagnosis of this de novo complex translocation and, subsequently, elected to terminate the pregnancy. Post-mortem examination revealed a 23–week fetus with intrauterine growth retardation. The identical chromosome rearrangement was subsequently confirmed in cultured fibroblasts from skin and cord obtained from the abortus. To our knowledge, this is the first report where routine prenatal diagnosis revealed a fetus with a balanced complex chromosomal rearrangement involving four chromosomes of de novo origin. 相似文献
110.