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161.
FN Karanu TC McGuire WC Davis TE Besser DP Jasmer 《Canadian Metallurgical Quarterly》1997,19(10):435-445
"Freezing" is a sudden, unforeseen state of immobility occurring independently of L-Dopa dosage timing and often presents in connection with walking, speech and hand movements. The immobility results from deficits in initiating or simultaneously and sequentially executing movements, in correcting inappropriate movements or planning movements. However, since the progression of motor activity is strongly dependent upon external stimuli, the patient can overcome the freezing phenomena with the aid of certain stimuli or subjective strategies. No consistent relationships have been found with respect to age, length of illness, L-dopa dosis or L-dopa treatment. Neurotransmitter models to explain the freezing phenomena are: a noradrenalin deficiency in locus coeruleus or alternately a dopamine deficiency in substantia nigra, pars compacta, which can possibly be coupled with a GABA deficiency in substantia nigra, pars reticulata. In addition to optimal drug therapy, patients require physiotherapeutical and ergotherapeutical assistance to develop subjectively effective strategies in counteracting freezing during everyday activities. 相似文献
162.
Emission spectroscopy measurements of Balmer-β and Balmer-γ line profiles are carried out to study their line shapes and line intensities as a function of discharge parameters such as fill pressure (3-7 mbar) and input power (200-400 W). A technique based on determining the relative intensities of neutral atomic hydrogen emission lines is used to evaluate the electron temperature, whereas the electron density is extracted from the Stark broadening (FWHM) of the Hβ emission profile. It is found that both the emission intensity and the broadening of the Balmer-β and Balmer-γ lines exhibit significant dependence on the fill pressure in the same manner. However, both the emission intensity and broadening of the Hβ line exhibit a weak dependence on input power in contrast to the Hγ emission line. Based on optical measurements reported here, plasma discharge parameters can be selected to optimize the electron temperature and density. 相似文献
163.
The concept of political risk has been defined from the perspective of developed-country multinational enterprises (MNEs) and has mainly focused on the political and regulatory perils in developing host countries. However, we have limited understanding of how emerging market firms perceive political risk in international marketplaces. Adopting a case study method, we examine how Chinese MNEs perceive political risk when operating in developed and developing host countries, specifically, the European Union (EU) and Africa. Our findings show that Chinese MNEs regard their home-country origin and industry-specific restrictions as major political risks in the EU. By contrast, they consider the volatile political environment in some African countries as the main source of political risk. In addition to the sharp contrast in the political and regulatory environment between the EU and African states, Chinese MNEs commonly encounter political risks in both markets due to their own behaviour. 相似文献
164.
Learning through international acquisitions: The process of knowledge acquisition in China 总被引:2,自引:0,他引:2
Abstract and Key Results
相似文献
• | Research on the process of knowledge learning and absorption in acquisition context has emerged recently. Yet relatively less attention has been paid to the process of knowledge transfer and learning and its impact on successful acquisitions. |
• | This paper adopts a process perspective’ to investigate this issue. Based on four international acquisitions in China, it generates new theoretical propositions as well as practical managerial implications. |
• | Results reveal the types of knowledge acquired and how it is transferred and learnt to contribute to the success of international acquisitions. The knowledge acquisition and learning process in international context involve three stages: knowledge assessment, knowledge sharing and knowledge assimilation. |
• | Foreign acquirers tend to acquire complementary knowledge from local targets, adopt dual management structure and facilitate communications with local personnel in order to achieve the success of acquisitions and future operations. |
165.
Programmable broadband rf filters are demonstrated using a compact retroreflective optical design with an acousto-optic tunable filter and a chirped fiber Bragg grating. This design enables fast 34 micros domain analog-mode control of rf filter time delays and weights. Two proof-of-concept filters are demonstrated including a two-tap notch filter with >35 dB notch depth and a four-tap bandpass filter. Both filters have 2-8 GHz tunability and a 34 micros reset time. 相似文献
166.
Amjad Ali Farrukh Shehzad Bashir Rizwan Raza Asia Rafique Muhammad Kaleem Ullah Farah Alvi Muhammad Afzal Moinuddin Ghauri Lyubov M. Belova 《International Journal of Hydrogen Energy》2018,43(28):12900-12908
The efficient conversion of solid carbon fuels into energy by reducing the emission of harmful gases is important for clean environment. In this regards, direct carbon fuel cell (DCFC) is a system that converts solid carbon directly into electrical energy with high thermodynamic efficiency (100%), system efficiency of 80% and half emission of gases compared to conventional coal power plants. This can generate electricity from any carbonaceous fuel such as charcoal, carbon black, carbon fiber, graphite, lignite, bituminous coal and waste materials. In this paper, ternary carbonate-samarium doped ceria (LNK-SDC) electrolyte has been synthesized via co-precipitation technique, while LiNiCuZnFeO (LNCZFO) electrode has been prepared using solid state reaction method. Due to significant ionic conductivity of electrolyte LNK-SDC, it is used in DCFC. Three types of solid carbon (lignite, bituminous, sub-bituminous) are used as fuel to generate power. The X-ray diffraction confirmed the cubic crystalline structure of samarium doped ceria, whereas XRD pattern of LNCZFO showed its composite structure.The proximate and ultimate coal analysis showed that fuel (carbon) with higher carbon content and lower ash content was promising fuel for DCFC. The measured ionic conductivity of LNK-SDC is 0.0998 Scm?1 and electronic conductivity of LNCZFO is 10.1 Scm?1 at 700 °C, respectively. A maximum power density of 58 mWcm?2 is obtained using sub-bituminous fuel. 相似文献
167.
Noveed Ejaz Liaqat Ali Furqan Ahmed Khalid Mahmood Ghauri A. Nusair Khan 《Journal of Thermal Spray Technology》2017,26(5):913-928
A novel thermal barrier coating system was formulated to resist hot corrosion environments. In this coating system, 5% CaZrO3 was added to conventional yttria-stabilized zirconia (YSZ). The above composite coating system was compared with the standard YSZ system in the presence of a mixture of 50% Na2SO4 and 50% V2O5 at 950 °C. The results demonstrated that the lifetime of the CaZrO3-added composite system in this highly hostile environment was longer compared with the standard YSZ system. This is due to the fact that the preferential reaction of NaVO3 shifted from yttria to calcia, forming CaV2O4 instead of YVO4. The preferential reactions are discussed in terms of free energy changes and acid–base theory of molten salts with ceramic oxides. Furthermore, calculations of lattice distortion also proved that the CaZrO3-added composite system demonstrated less distortion, thus increasing the overall lifetime of the coating system. 相似文献
168.
Naresh R. Pandit Gary A. S. Cook Feng Wan Jonathan V. Beaverstock Pervez N. Ghauri 《Management International Review》2018,58(6):935-967
This study’s objective is to compare cluster economies and diseconomies for multinational enterprises (MNEs) and uninational enterprises (UNEs) within the London financial services cluster. In contrast to the implicit assumption of the cluster participation literature that the economies and diseconomies of clusters are valued similarly by all firms, we find that economies relating to social capital and labour market pooling are equally important to MNEs and UNEs, economies relating to local competition and diseconomies relating to congestion costs are more important to MNEs than to UNEs, and economies relating to the reputational effects of locating in a world-leading cluster and access to specialised suppliers are more important to UNEs than to MNEs. That MNEs and UNEs do not experience cluster economies and diseconomies in the same way indicates that both cluster participation theory and international business theory need augmentation to recognise that cluster incumbents benefit and suffer from cluster membership differently. 相似文献
169.
Using cell recycling batch fermentations to validate a setup for cellulosic ethanol production 下载免费PDF全文
170.
Hot corrosion behavior of double ceramic layered CaZrO3/Yttria‐stabilized zirconia coatings 下载免费PDF全文
Naveed Ejaz Liaqat Ali Furqan Ahmed Gul Awan Khalid Mehmood Ghauri Aamer Nusair 《International Journal of Applied Ceramic Technology》2018,15(1):53-62
A novel double ceramic layered (DCL) CaZrO3/Yttria‐stabilized zirconia (YSZ) thermal barrier coatings (TBCs) was designed for improved service life against sulfate vanadate hot corrosion as compared with that of YSZ single layered coating. The hot corrosion behavior of DCL CaZrO3/YSZ coatings was studied at 950°C after dry spreading 50%Na2SO4+50%V2O5 mixture onto a coated surface. The CaZrO3 as the topmost layer in DCL CaZrO3/YSZ coatings, served as a sacrificial layer during sulfate vanadate hot corrosion protecting the underneath YSZ coating. The corrosion reactions in this case were sluggish due to the initial formation of low melting point meta‐calcium vanadate (CaV2O6) that isothermally transformed to higher melting point calcium vanadates having higher calcia (CaO) content. The corrosion reaction products sealed the top surface, impeding the oxygen movement and eventually retarded the thermally grown oxide (TGO) growth. The sulfate vanadate hot corrosion life of the DCL CaZrO3/YSZ coatings was observed to be more than double as compared with single ceramic layered YSZ coatings. 相似文献