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排序方式: 共有653条查询结果,搜索用时 15 毫秒
51.
Late psychosocial improvement in a case of severe head injury with bilateral fronto-orbital lesions.
Describes the results of a 19-yr follow-up study of a head-injured female patient. At age 17 yrs, the S sustained a blunt head trauma with bilateral fronto-orbital lesions verified by late regional cerebral blood flow. The S presented an extreme state of regression for many months after injury. During the first posttraumatic years no behavioral disorders were reported, but after the 5th yr lack of control, including sexual disinhibition, and lack of motivation became severe problems. More than 10 yrs after the accident, a partner applied a simple program of behavioral modification to the S. After 2 yrs of rigid training, an unexpected improvement in psychosocial adaptation took place. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
T. M. Yurieva G. N. Kustova T. P. Minyukova E. K. Poels A. Bliek M. P. Demeshkina L. M. Plyasova T. A. Krieger V. I. Zaikovskii 《Materials Research Innovations》2001,5(1):3-11
Cu/SiO2, Zn/SiO2 and Cu-Zn/SiO2 samples have been prepared by the homogeneous deposition-precipitation method. The samples were analyzed by thermal analysis,
X-ray diffraction and infrared spectroscopy after various heat treatments and compared with data obtained for several minerals.
It has been shown that interaction between the components occurs through formation of hydrosilicates. Copper-silica system
at a Cu:Si ratio ≤ 1, gives rise to a hydrosilicate stable up to a calcination temperature of 930 K resembling the mineral
Chrisocolla; at higher ratios a hydroxonitrate (gerhardite type) is also formed. Zinc-silica interaction produces two hydrosilicates
such as a well crystallized Hemimorphite at Zn:Si = 2 and highly dispersed Zincsilite at Zn:Si ≤ 0.75, both stable up to 1073
K. The Zincsilite structure consists of three layered sheets (an octahedral layer sandwiched by two tetrahedral ones) like
the Stevensite mineral group. For the copper-zinc-silica system no copper hydrosilicate is formed. Copper merely enters the
Zincsilite structure independenly of the applied (Cu + Zn):Si ratio. Resulting layered copper-zinc hydrosilicate may be described
by formula
Znx-yCuy(Zn3-x–zCuz–y▪x)[Si4O10](OH)2.nH2O,
where Zn3-x-zCuz-y– ions are located in octahedral sites, Znx-yCuy–ions in the interlayer; ▪x are vacancies in the layers. Copper and zinc in excess of the Zincsilite ratio of Me:Si = 0.75, gives rise to copper and
copper-zinc hydroxonitrates.
Received: 7 November 2000 / Reviewed: 23 January 20001 / Accepted: 23 January 2001 相似文献
53.
Krieger U.R. Muller-Clostermann B. Sczittnick M. 《Selected Areas in Communications, IEEE Journal on》1990,8(9):1630-1648
The authors describe a computational approach for modeling and analyzing modern communication systems based on numerical methods for Markov chains. Advanced direct and iterative procedures for the calculation of the stationary distribution of a homogeneous discrete- or continuous-time Markov chain with finite state space are presented. They are implemented in a convenient software tool called MACOM for interactive modeling and performance evaluation of communication systems. MACOM provides the user with a predefined markovian model world describing modern telecommunication networks with adaptive routing schemes and advanced congestion-control mechanisms. The versatility of these algorithms is illustrated by their application to Markovian queuing models derived from telecommunications networks 相似文献
54.
55.
Alfons Schloemer Waldemar Godbersen und Max Ohm 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1940,79(4):337-344
Zusammenfassung Bericht über die gemeinsame Kontrolle des Groß-Berliner Buttermarktes durch die Kontrollorgane der amtlichen Lebensmittelkontrolle, den Gewerbe-Außendienst der Polizei und die Preußische Landesanstalt zusammen mit den Buttersachverständigen der Hauptvereinigung der deutschen Milch- und Fettwirtschaft, sowie des Milch- und Fettwirtschaftsverbandes Kurmark im Jahre 1939; ambulante Kontrolle, Methodik der polizeilichen Probenahme, Begleitbogen, Prüfung der Butterproben bezüglich Kennzeichnung, Form, Gewicht, Perforierung, Wassergehalt, Verfälschung mit fremden Fetten sowie Sinnenprüfung; Beurteilung der Proben auf Grund der verschiedenen, hier angeführten Gesetze, Verordnungen und Anordnungen. 相似文献
56.
Rodriguez-Cassola M. Baumgartner S. V. Krieger G. Moreira A. 《Geoscience and Remote Sensing, IEEE Transactions on》2010,48(2):781-794
57.
Pawe Maksimowski Maciej Duda Waldemar Tomaszewski 《Propellants, Explosives, Pyrotechnics》2011,36(4):320-326
2‐Acetyl‐4,6,8,10,12‐pentanitro‐2,4,6,8,10,12‐hexaazaisowurtzitane (PNAIW) is formed in the last step of nitration of acetyl isowurtzitane derivatives. The amount of the PNAIW formed depends on the conditions of the nitration reaction (temperature, time, and nitrating mixture used) and on the type of the starting acetyl intermediate. The highest PNAIW yields (30 %) were obtained by nitrating 2,6,8,12‐tetraacetylhexaazaisowurtzitane (TAIW) at 60 °C for half an hour using HNO3/H2SO4 nitrating mixture. HPLC, NMR, FTIR, and DSC measurements were used in the study and their results are reported. 相似文献
58.
We have utilized the Hewlett‐Packard LC/ESI‐MS technology to store electronic records of total ion current profiles of molecular species of various natural and peroxidized phospholipids of native and auto‐oxidized plasma lipoproteins before and after digestion with secretory phospholipase A2 (sPLA2). The present report illustrates the successful utilization of the stored data in several originally un‐intended applications, including chemical, physico‐chemical and enzymatic alterations of the lipoprotein lipids. The inclusion of lipid samples from enzyme and control incubations adds a dynamic aspect to multidimensional lipidomic analysis of plasma lipoproteins. 相似文献
59.
60.
Glaucio H. Paulino Kyoungsoo Park Waldemar Celes Rodrigo Espinha 《International journal for numerical methods in engineering》2010,84(11):1303-1343
Dependence on mesh orientation impacts adversely the quality of computational solutions generated by cohesive zone models. For instance, when considering crack propagation along interfaces between finite elements of 4k structured meshes, both extension of crack length and crack angle are biased according to the mesh configuration. To address mesh orientation dependence in 4k structured meshes and to avoid undesirable crack patterns, we propose the use of nodal perturbation (NP) and edge‐swap (ES) topological operation. To this effect, the topological data structure TopS (Int. J. Numer. Meth. Engng 2005; 64 : 1529–1556), based on topological entities (node, element, vertex, edge and facet), is utilized so that it is possible to access adjacency information and to manage a consistent data structure in time proportional to the number of retrieved entities. In particular, the data structure allows the ES operation to be done in constant time. Three representative dynamic fracture examples using ES and NP operators are provided: crack propagation in the compact compression specimen, local branching instability, and fragmentation. These examples illustrate the features of the present computational framework in simulating a range of physical phenomena associated with cracking. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献