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81.
82.
E. V. Pinneker B. I. Pisarski S. E. Pwalowa 《Isotopes in environmental and health studies》2013,49(3-4):313-320
Abstract The isotopic composition (D, 18O, 87Sr, 3He) of thermal and mineral waters of Mongolia is discussed. The Sr-isotope ratio depends on the rock's contact. Near the Chubsugul-lake 3He-/4He-values are high. A certain similarity between the waters of Mongolia and those of East Siberia can be derived from the obtained data. 相似文献
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危地马拉是缅甸之外的另一个翡翠的商业性产地,危地马拉翡翠通常是多种矿物成分的集合体,其矿物组成具有特色,与缅甸翡翠的不同。以危地马拉紫色和灰绿色翡翠为研究对象,通过激光拉曼光谱测试分析,对其结构特征及共生矿物组成特点进行了研究。结果表明,危地马拉翡翠中的主要组成矿物为硬玉,并伴有多种共生矿物。危地马拉翡翠的共生矿物包括五类,其中深色共生矿物为角闪石,白云石,绿辉石和绿泥石,浅色共生矿物为磷灰石。其中角闪石,白云石,绿辉石和绿泥石也是缅甸翡翠中常见的共生矿物,而磷灰石在缅甸翡翠中几乎不可见。 相似文献
86.
The paper is concerned with describing an investigation of information usage in the control of colliery operations. The premise of the work is that to make the most of new information retrieval technology currently being installed in collieries research in needed to provide compatible advances in methods of information usage. The approach adopted was to construct a continuous simulation model using system dynamics capable of providing a laboratory assessment of alternative managerial control policies based on alternative sources and levels of aggregation of information.The model developed represents a typical colliery situation composed of three working coal-faces and incorporating planning, production, development and manpower sectors. The face sectors transform coal reserves to mined coal output, under manpower constraints and geological shocks, and these are all interlinked by means of allocation policies for manpower and machine shifts.A range of policies for the exercise of control through these allocations are considered subject to a range of shocks. It is concluded that, although there are difficulties in designing single policies which are universally best, there are clear advantages associated with fully integrated colliery policies based on information inputs from all aspects of the operations. 相似文献
87.
Milad Javanmard Hossein Ali Asadi-Gharneh Pejman Nikneshan 《Natural product research》2018,32(14):1738-1743
Dog rose (Rosa canina L.) is a wild native species in Iran, with a significant genetic diversity. This plant serves as a rich source of vitamin C, anthocyanins, phenolic contents and carotenoids. Rose hips have been used in several food products, as well as perfumery and cosmetics industries. In this research, we investigate biochemical characteristics of five dog rose ecotypes (Kopehjamshid, Zarneh, Miyankish, Aghcheh and Sadeghiyeh), that were collected from the central part of Iran (Isfahan province). Amounts of vitamin C, total carotenoids, total phenolic contents, total anthocyanins, macro and micro minerals were measured. Seed oil are extracted by soxhlet method and analysed by gas chromatography. The macro and micro minerals levels in the fruit vary significantly among these regions. The results of this study demonstrate that dog rose have great diversity and can be used in breeding programmes in order to increase nutrient values as a food resource additive. 相似文献
88.
O. F. Shlensky M. T. Chirkov N. A. Zyrichev 《Journal of Thermal Analysis and Calorimetry》1992,38(4):981-988
Kinetic curves of thermal decomposition and synthesis of mineral salts are obtained in the conditions of rapid heating approaching the heating conditions in a low-temperature plasma flow. The kinetic characteristics are used in calculations of transformations in the path of a chemical plasma reactor.
Zusammenfassung Für thermische Zersetzung und Synthese von Mineralsalzen wurden die kinetischen Kurven unter den Bedingungen schnellen Aufheizens in Annäherung der Aufheizbedingungen in einem Niedertemperatur-Plasmastrom ermittelt. Die kinetischen Eigenschaften wurden zur Berechnung der Umwandlungen bei einem chemischen Plasmareaktor verwendet.相似文献
89.
Bioreactors serve a central role in biotechnological processes by providing the link between starting materials and final
products. In most biological systems, there are complex series of reactions that must be optimized and coordinated in a very
specific environment. Despite the complexity of biocatalytic processes, there is usually a rate-limiting step controlling
the reaction, as well as a few secondary limitations. These limitations provide the basis for process design and bioprocess
equipment specifications. The EIMCO Slurry Bioreactor has been designed to overcome these limitations encountered during the
bio-oxidation of refractory gold ores and concentrates and hazardous waste bioremediation. 相似文献
90.
尼尔雌醇对去卵巢大鼠骨元素代谢的影响 总被引:2,自引:3,他引:2
用测定骨元素含量的方法,分析了尼尔雌醇对去卵巢大鼠骨元素代谢的影响。将健康4月龄雌性SD大鼠35只随机分成正常对照组、假去卵巢组、去卵巢组和去卵巢 尼尔雌醇组。结果表明,去卵巢大鼠骨Ca、Mg、S、Mn、Zn含量显著降低,P含量显著增加。尼尔雌醇可使去卵巢大鼠降低的骨Ca、Mg、S、Mn、Zn含量显著回升,骨P含量显著回降。尼尔雌醇可纠正去卵巢所致的骨元素代谢紊乱。 相似文献