取代苯甲酸葡萄糖酯的合成及生物活性

以两种方法合成了10个取代苯甲酸葡萄糖酯类化合物，一是相转移催化法，二是在三忆胺的存在下，取代苯甲酸与溴代葡萄糖反应，该种合成糖酯的方法未见文献报道，取代苯甲酸葡萄糖酯的结构由IR、MS、^1H NMR和元素分析确认。对化合物的抗病毒活性测试结果发现，其中有两个化合物具有一定的抑制TMV的活性。     

Fourier coefficient design of stepped impedance transmission line networks

The conventional method of designing stepped impedance transmission line networks from gain functions requires the use of a factorization process to obtain a passive input impedance, and then the application of Richards Theorem to determine the element values. A new technique is presented based upon the determination of the Fourier coefficients of the return loss function from which the element values may be obtained immediately for the minimum phase reflection coefficient without any factorization process or synthesis procedure. It is believed that this new technique may be extended directly to the design of mixed lumped-distributed transmission line networks whereas the conventional approach may not.     

EFFECT OF MASS FLUX AND SYSTEM PRESSURE ON TWO-PHASE FRICTION MULTIPLIER

A horizontal boiling water loop was used to obtain pressure drop and heat transfer data for two-phase steam-water flow for pressures of up to 825 kPa. The data were used to examine the predictions of the separated flow model using the Lockhart-Martinelli method of estimating the two-phase friction multiplier.

The influence of mass flux on the two-phase friction multiplier has been reported for high pressure systems by many workers. The present work confirms the existence of this influence at low pressures as well. System pressure is also found to be a parameter. A correlation for the two-phase friction multiplier, incorporating the effects of mass flux and pressure, is presented here. The correlation has been tested against data from two independent sources. The predictions have been found to be in very good agreement with the data.     

Therapist retrospective recall impasses in long-term psychotherapy: A qualitative analysis.

Twelve experienced therapists completed a questionnaire, and 8 of the 12 were then interviewed about their experiences with a therapeutic impasse that ended in the termination of therapy. Data were analyzed using a qualitative methodology. Results indicated that most of the clients were anxious and depressed with personality disorders and interpersonal problems. Therapists perceived impasses as having a profound negative impact on both clients and therapists. Variables associated with impasses in a majority of the cases were a client history of interpersonal problems, a lack of agreement between therapists and clients about the tasks and goals of therapy, interference in the therapy by others, transference, possible therapist mistakes, and therapist personal issues. Implications for training, practice, and research are provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Realisation of microwave brune sections

Microwave Brune sections are used for realisation of real-frequency zeros of transmission. Previous realisations of this section involve inconvenient structures, and two new realisations are described which possess considerable practical advantages.     

Treatment of meats with ionising radiations. XV.—Irradiation of beef from barley-fed animals

Joints of ‘barley beef’, irradiated at a dose level of 0.4 Mrad., were stored at 2° in plastic packages of differing gas permeabilities. Bacterial growth was reduced by the lack of oxygen and/or the accumulation of carbon dioxide. The irradiated meat remained unspoiled for at least 84 days. The useful shelf-life of the beef can be extended greatly by irradiation, but the undesirable colour changes resulting from the exclusion of oxygen remains a serious drawback.