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1.
根据工业及家庭供暖的要求,设计并研制成一种新型的热流量计,它采用方便而新颖的采集信息方式,并使用CPU精确实时的进行控制和运算,保证了热流量计的精确、实时和“分户计量”。  相似文献   
2.
The number of organizations using teamwork is increasing. In this context, group potency has emerged as a key construct in group research. Moreover, in the last decades, information and communication technologies (ICT) have allowed organizations to form virtual teams. Consequently, a considerable amount of research has analysed the functioning of virtual teams. We focus on intragroup conflict as a relevant antecedent of potency in computer-mediated communication groups. Specifically, the aim of this research is to examine the role of ICT in the relationship between intragroup conflict and group potency in a longitudinal study. A laboratory experiment was carried out comparing 44 groups working in two communication media (face-to-face and computer-mediated communication). The groups developed a project over a one-month period. The results show that communication media play a moderator role between intragroup conflict (relationship and task conflict) and group potency. Implications of these results are discussed.  相似文献   
3.
In today's highly interconnected, uncertain and dynamic business environment, team boundary spanning has become an important determinant of the performance of new product development (NPD) projects. Despite the positive evidence supporting the use of boundary spanning activities by NPD teams, little is still known about how boundary spanning teams become high-performance teams. The current study advances research on this subject by examining the mediating effect of team potency on the relationship between team boundary spanning and new product performance, as well as the moderating effects of team size and functional diversity on the relationship between team boundary spanning and team potency. Data from a time-lagged survey study of 140 NPD projects found that team boundary spanning can promote team potency that, in turn, results in greater new product quality and new product creativity. The positive effect of team boundary spanning on team potency was found to be more pronounced for NPD teams of medium size and high levels of functional diversity.  相似文献   
4.
The use of online collaboration tools for virtual teamwork has been studied extensively, but mainly at the individual-level. We decided to examine the effect of macro-level factors (i.e., team attributes) and applied hierarchical linear modeling analysis to a sample of data collected from 96 individuals nested in 34 virtual teams. Our results suggested that the development of behavioral e-collaboration intentions by individual virtual team members was affected by their perceptions about the system, as described by individual-level IT use theories, and macro-level factors pertaining to the team. The collaboration technology was perceived to be less useful when employed to communicate with social loafers; and collective social loafing negatively influenced the teams’ potency assessments. After controlling for individual-level perceptions of system usefulness, team potency augmented team members’ intentions to use the online collaboration technology with similar teams. It also improved team performance.  相似文献   
5.
探讨了国有企业实行效能监察工作创新的方法,为推动效能监察向更深层次发展提供参考。  相似文献   
6.
The extensive application of herbicides in crop cultivation has indisputably led to the emergence of weed populations characterized by multiple herbicide resistance (MHR). This phenomenon is associated with the enhanced metabolism and detoxifying ability of endogenous enzymes, such as phi class glutathione transferases (GSTFs). In the present work, a library of mutant GSTFs was created by in vitro directed evolution via DNA shuffling. Selected gstf genes from the weeds Alopecurus myosuroides and Lolium rigidum, and the cereal crops Triticum durum and Hordeum vulgare were recombined to forge a library of novel chimeric GSTFs. The library was activity screened and the best-performing enzyme variants were purified and characterized. The work allowed the identification of enzyme variants that exhibit an eight-fold improvement in their catalytic efficiency, higher thermal stability (8.3 °C) and three-times higher inhibition sensitivity towards the herbicide butachlor. The crystal structures of the best-performing enzyme variants were determined by X-ray crystallography. Structural analysis allowed the identification of specific structural elements that are responsible for kcat regulation, thermal stability and inhibition potency. These improved novel enzymes hold the potential for utilization in biocatalysis and green biotechnology applications. The results of the present work contribute significantly to our knowledge of the structure and function of phi class plant GSTs and shed light on their involvement in the mechanisms of MHR.  相似文献   
7.
以从新鲜牛奶中筛选出的乳酸链球菌KY-2为出发菌株,采用二剂量法检测发酵液中Nisin效价,通过单因子试验和正交设计对该菌株产Nisin发酵培养基进行优化.结果表明:该茵株产Nisin的最适碳源、氮源和磷源组合为(%):蔗糖0.8,蛋白胨2.0,酵母膏1.0,K2HPO4 0.9.优化后效价为957.95 IU/mL,比优化前(812.11 IU/mL)提高了18.0%.  相似文献   
8.
A ranking system for veterinary medicinal products and coccidiostat feed additives has been developed as a tool to be applied in a risk-based approach to the residue testing programme for foods of animal origin in the Irish National Residue Control Plan (NRCP). Three characteristics of substances that may occur as residues in food are included in the developed risk ranking system: Potency, as measured by the acceptable daily intake assigned by the European Medicines Agency Committee for Medicinal Products for Veterinary Use, to each substance; Usage, as measured by the three factors of Number of Doses, use on Individual animals or for Group treatment, and Withdrawal Period; and Residue Occurrence, as measured by the number of Non-Compliant Samples in the NRCP. For both Number of Doses and Non-Compliant Samples, data for the 5-year period 2008–12 have been used. The risk ranking system for substances was developed for beef cattle, sheep and goats, pigs, chickens and dairy cattle using a scoring system applied to the various parameters described above to give an overall score based on the following equation: Potency × Usage (Number of Doses + Individual/Group Use + Withdrawal Period) × Residue Occurrence. Applying this risk ranking system, the following substances are ranked very highly: antimicrobials such as amoxicillin (for all species except pigs), marbofloxacillin (for beef cattle), oxytetracycline (for all species except chickens), sulfadiazine with trimethoprim (for pigs and chickens) and tilmicosin (for chickens); antiparasitic drugs, such as the benzimidazoles triclabendazole (for beef and dairy cattle), fenbendazole/oxfendazole (for sheep/goats and dairy cattle) and albendazole (for dairy cattle), the avermectin ivermectin (for beef cattle), and anti-fluke drugs closantel and rafoxanide (for sheep/goats); the anticoccidials monensin, narasin, nicarbazin and toltrazuril (for chickens). The risk ranking system described is a relatively simple system designed to provide a reliable basis for selecting the veterinary medicinal products and coccidiostat feed additives that might be prioritised for residue testing.  相似文献   
9.
以两性霉素B粗制品为原料,以产品中未知杂质含量、效价及质量收率为考察对象,探索了两性霉素B结晶的操作条件。实验发现,以20%N,N-二甲基甲酰胺-乙醇(75%)水溶液为溶剂体系、pH为5~6、75%乙醇水溶液加入量为3~4倍滤液体积时可得到杂质含量低、效价和质量收率较高的两性霉素B产品。  相似文献   
10.
Context: The difference between the chemical polarities of the two categories of active chemical constituents in Chinese angelica volatile oil (CAVO) and Chinese angelica water extract (CAWE) greatly limit the development and clinical application of Chinese angelica preparation.

Object: The aim of this study is to design and prepare a “whole Chinese angelica” microemulsion (WCAM) that contains both CAVO and CAWE and at the same time to evaluate it in vivo and in vitro.

Materials and methods: CAVO and CAWE extracted from Chinese angelica were used as the oil and aqueous phases, respectively, to prepare the WCAM; its physicochemical property was observed, and its drug potency and oral bioavailability were evaluated.

Results: The formula of the WCAM was optimized as Tween-80:ethanol:CAVO:CAWE?=?3:3:1:40. The droplet size of the WCAM was 72.64?nm and the WCAM was proved to be physicochemically stable when it was kept at 0?°C, 4?°C, 25?°C and 40?°C for 3 months. The WCAM could markedly prolong blood clotting time, decrease whole blood viscosity and whole blood reduced viscosity at different shear rates, and improve hemorheological parameters. The results of the pharmacokinetic evaluation show that the AUC0–7 of the WCAM was 4510.66 and was about 4.41-fold compared to that of danggui concentrated pills (an existing Chinese angelica pharmaceutical preparation).

Conclusion: It can be concluded, that the WCAM is a promising Chinese angelica preparation that has great prospects in the treatment of dysmenorrhea and irregular menstruation.  相似文献   
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