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61.
R Manjarres-García GE Escorcia-Salas ID Mikhailov J Sierra-Ortega 《Nanoscale research letters》2012,7(1):489
ABSTRACT: The electronic states of a singly ionized on-axis double-donor complex (D2+) confined in two identical vertically coupled, axially symmetrical quantum dots in a threading magnetic field are calculated. The solutions of the Schrodinger equation are obtained by a variational separation of variables in the adiabatic limit. Numerical results are shown for bonding and antibonding lowest-lying artificial molecule states corresponding to different quantum dot morphologies, dimensions, separation between them, thicknesses of the wetting layers, and magnetic field strength. 相似文献
62.
ABSTRACT: BACKGROUND: Food and nutritional care quality must be assessed and scored, so as to improve health institution efficacy. This study aimed to detect and compare actions related to food and nutritional care quality in public and private hospitals. METHODS: Investigation of the Hospital Food and Nutrition Service (HFNS) of 37 hospitals by means of structured interviews assessing two quality control corpora, namely nutritional care quality (NCQ) and hospital food service quality (FSQ). HFNS was also evaluated with respect to human resources per hospital bed and per produced meal. RESULTS: Comparison between public and private institutions revealed that there was a statistically significant difference between the number of hospital beds per HFNS staff member (p = 0.02) and per dietitian (p < 0.01). The mean compliance with NCQ criteria in public and private institutions was 51.8% and 41.6%, respectively. The percentage of public and private health institutions in conformity with FSQ criteria was 42.4% and 49.1%, respectively. Most of the actions comprising each corpus, NCQ and FSQ, varied considerably between the two types of institution. NCQ was positively influenced by hospital type (general) and presence of a clinical dietitian. FSQ was affected by institution size: large and medium-sized hospitals were significantly better than small ones. CONCLUSIONS: Food and nutritional care in hospital is still incipient, and actions concerning both nutritional care and food service take place on an irregular basis. It is clear that the design of food and nutritional care in hospital indicators is mandatory, and that guidelines for the development of actions as well as qualification and assessment of nutritional care are urgent. 相似文献
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64.
新型发光、无机和有机纳米型染料主要用于聚对苯二甲酸乙二醇酯(PET)纤维的制备。PET纤维是制作用于预警和安保系统的纤维织物的原材料。具有发光性质的纳米染料的制备方法主要有两种:一种为自下而上,沉淀法合成;另一种为自上而下,通过反应型研磨得到。下述的纳米染料是硫化锌(ZnS),同时还掺杂有铜或锰、铝酸锶,还可掺杂铕和镝。此外,还对有机染料和颜料(醛连氮和二萘嵌苯)进行研究,还将其包裹于硅纳米粒子中并进行相关研究。制得的纳米粒子混入高分子熔体中,通过熔融挤出得到成品丝。该过程中所使用的纳米颜料可混入母粒中,也可制成液状使用。最后进行成品丝变形工艺研究,并加工成纺织面料。纳米发光颜料的加入实现了低染料剂量下的高发光性。与已投入使用的传统体系相比,采用纳米发光颜料的体系具有更好的光、热和湿牢度。 相似文献
65.
孟加拉侯赛化学有限公司 《硫酸工业》2001,(3):49
孟加拉侯赛化学有限公司(HCCL)150kt/a粒状普钙(GSSP)工程是由南化集团设计院和中国化工建设总公司共同承包的化肥交钥匙工程.该工程包括60kt/a硫磺制酸及150kt/a粒状普钙,硫酸工艺采用快速熔硫、自然沉降和"3+1”两转两吸工艺,普钙采用湿磨磷矿、磷矿浆混化、皮带化沉、造粒和干燥工艺.中方主要负责工程的设计,主要设备、材料的采购,设备安装和开车指导;外方负责工程的土建设计,施工及设备、材料的安装工作.工程造价约406万美元(不含外方负责工作费用).目前,已完成工程的详细设计和主要设备的采购,预计工程将于2002年8月完工投产,工程建成后,可极大缓解该国的化肥紧缺状况.
(南化集团设计院邱世庭) 相似文献
66.
杂质分离器是一种有效的降低纤维杂质的工具。搭配几种灵敏感应器模块的系统能有效地检测和去除几类杂质。这样的系统也可成功地用于轧棉工序。 相似文献
67.
Defects in CVDZnS 总被引:1,自引:0,他引:1
FU Liganga b Lü Fanxiua WANG Xuewub WEI Naiguangb a School of Materials Science Engineering University of Science Technology Beijing Beijing China b Beijing Guojing Infrared Optical Technology Co.Ltd. General Research Institute for Nonferrous Metals Beijing China 《稀有金属(英文版)》2011,30(4):387-391
Defects seriously influence the optical properties and mechanical properties of CVDZnS.The deposition technique was introduced and experiment methods such as SEM,TEM and OM were adopted to study the defects:hexagonal phase,abnormally large grains,micro-cracks,micro-pores and impurities.The microstructures of these defects were observed,and the formation mechanisms of these defects were analyzed.Hexagonal ZnS as an impurity causes anisotropy in different directions with different refraction indexes and increases the scattering of CVDZnS.Increasing the deposition temperature can inhibit the formation of the hexagonal phase.The main reason for the growth of abnormally large grains in CVDZnS is high deposition rate.The lower deposition temperature increases growth stress in CVDZnS,which consequently results in the bowing of CVDZnS plates,and introduces microscopic defects such as grain blending and micro-cracks in the crystal.Micro-pores and impurities are induced by high reactant concentration in the local deposition chamber,which can be avoided by improving the gas flowing so as to make the concentration more uniform. 相似文献
68.
69.
Moncia García Fernández 《世界建筑导报》2010,25(1)
项目地点:西班牙塞埃欣项目类型:景观设计开工日期:2005年12月该项目获2005年豪瑞可持续建筑大奖赛欧洲地区提名奖 相似文献
70.
An automatic purge and trap apparatus, coupled to a GC-MS was used to study the seasonal variability of the volatile fraction of raw milk Manchego cheese. Both season and dairy significantly affected abundance of most volatile compounds. Most aldehydes, methyl ketones, n-alcohols, and secondary alcohols reached significantly higher concentrations in spring cheeses. Branched chain alcohols showed significantly higher concentrations in autumn and winter cheeses, while significantly higher amounts of diketones were found in summer cheeses. Most ethyl esters reached higher concentrations in spring and winter cheeses and lower in autumn cheeses. Lower concentrations of alpha-pinene were found in spring cheeses, and higher amounts of limonene were observed in winter cheeses. Heptane and octane were significantly more abundant in summer cheeses. No significant seasonal differences were found either for quality or intensity scores. 相似文献