铌酸对酯化反应催化性能的研究

研究了新型固体酸催化剂铌酸对乙醇及异戊醇与乙酸酯化反应的催化性能、研究表明热处理温度对水洗法制备的铌酸催化剂的催化活性有显著影响,在350℃处理时活性达到极大值.与HZSM-5相比,铌酸催化剂不仅在乙醇和乙酸的气相酯化反应中表现出良好的催比性能,而且在异戊醇和乙醇的液相酯化反应中亦表现出较好的催化活性和稳定性.     

Serum N-terminal osteocalcin is a good indicator for estimating responders to hormone replacement therapy in postmenopausal women

To estimate the response to hormone replacement therapy (HRT) by bone metabolic markers, 36 patients with postmenopausal osteoporosis or osteopenia were studied to assess the correlation between percent baseline changes in lumbar bone mineral density (BMD) after 12 months and those in various bone metabolic markers after 3, 6, and 12 months of HRT. All the patients were treated with 0.625 mg of conjugated estrogen and 2.5 mg of medroxyprogesterone per day and continued for 12 months. BMD was significantly increased up to 4.19 +/- 0.87% after 6 months and 4.93 +/- 1.27% after 12 months of HRT (p = 0.0001 by analysis of variance). In accordance with this, changes in the levels of osteocalcin (p = 0.041), alkaline phosphatase (p = 0.0001), N-terminal osteocalcin (p = 0.0001), urinary excretion of pyridinoline/Cr (p = 0.0001), and deoxypyridinoline/Cr (p = 0.0001) were significantly decreased, respectively. Among these bone metabolic markers, only the change in the serum N-terminal osteocalcin at 3 months (r = 0.557, p = 0.0022), at 6 months (r = 0.470, p = 0.0184), and at 12 months (r = 0.545, p = 0.0061) significantly correlated with the change in BMD 12 months after HRT. The elution profiles of immunoreactive osteocalcin-related molecules in serum fractionated by reverse-phase high performance liquid chromatography revealed that the N-terminal fragment as well as the intact osteocalcin molecule decreased after 3 months of HRT. These results demonstrate that N-terminal osteocalcin is a suitable predictor for estimating good responders to HRT in postmenopausal women.     

紫草色素的研究

紫草色素原植物系紫草科Broaginaceae几种植物的根，又称紫根色素。该研究首次用人工栽培的硬紫草(Lithospermum erythrohizon Sieb.)的根，作了加工工艺和特性的研究。产品得率近1％，色价E 1^1Q5nm达150以，卫生指标符合有关规定，是种理想的脂溶性红色素。     

关于深冲薄钢板中的夹杂和成形性的商榷

对深冲薄钢板大生产的全工艺过程进行了跟踪，研究了ＷＹ０８ＡｌＡ薄钢板中Ａｌ＿２Ｏ＿３的形成，形态以及它们对冷轧成品的深冲性能和冲压小件的冲压成形废品率的影响。     

带钢跑偏控制用电液伺服阀的修理与调试

本文介绍了带钢跑偏控制系统中电液伺服阀在使用中常见的几种故障，并针对每种故障产生的原因，具体介绍其修理和调试的方法     

The cholesterol-lowering properties of a psyllium-based breakfast cereal in hamsters

Hamsters were fed high fiber diets containing cellulose, wheat bran or psyllium. The psyllium was incorporated into high fiber, ready-to-eat (RTE) flakes that were used to formulate the test diet. All the diets contained 0.125% cholesterol. The study was terminated after three weeks. Food intake, weight gain and feed efficiency were not significantly different in the three groups. Serum total and HDL cholesterol levels were reduced significantly by the psyllium diet. Serum triglycerides were 26% lower in the hamsters fed psyllium but because of the large variation the difference did not reach statistical significance. Liver total cholesterol and cholesteryl ester levels were significantly lower in the hamsters fed psyllium. Liver triglycerides were highest in the psyllium-fed hamsters and liver phospholipid levels were similar in the three groups. Liver cholesterol and triglyceride levels were higher in hamsters fed cellulose than in those fed wheat bran. Psyllium formulated into an RTE cereal was effective in reducing serum and liver cholesterol levels in hamsters.     

Broadcast digital subscriber lines

The adoption of asymmetrical digital subscriber lines (ADSL) technology in conjunction with the broadcast digital subscriber lines (BDSL) proposed in this paper could provide a cost effective solution for the introduction of digital video services in the near term. BDSL provides the same digital broadcast video programs to all subscribers through existing twisted pair telephone loops. In this paper, the basics of telephone loop-based digital subscriber lines are first discussed. Then the potential of BDSL is explored in the twisted pair loop plant near end crosstalk (NEXT), far end crosstalk (FEXT), and white noise environment. The capability of BDSL is examined with different serving areas and transmit power levels. The possibility of using orthogonal quadrature amplitude modulation (QAM) to implement a zero guard-band BDSL system is studied. Computer BDSL performance simulations are then presented. The combination of high-bit-rate digital subscriber lines (HDSL), ADSL, and BDSL can provide telephone subscribers many digital broadband services     

Low-temperature growth of silicon-boron layer as solid diffusionsource for polysilicon contacted p+-n shallow junction

A new material, Si-B, is proposed as a solid diffusion source for fabrication of poly-Si contacted p⁺-n shallow junctions. The junction depth of the Si-B source diode has been measured and compared with that of a BF₂⁺-implanted poly-Si source diode. It was found that the Si-B source diode had a much shallower junction and was less sensitive to thermal budget than the BF₂⁺ source diode. This was attributed to the smaller surface concentration and diffusivity of boron in the silicon in Si-B source diodes. Regarding electrical characteristics of diodes with a junction depth over 500 Å, a forward ideality factor of better than 1.01 over 8 decades and a reverse-current density lower than 0.5 nA/cm² at -5 V were obtained. As the junction depth shrank to 300 Å, the ideality factor and reverse current density of diodes increased slightly to 1.05 and 1.16 nA/cm², respectively. These results demonstrated that a uniform ultrashallow p⁺-n junction can be obtained by using a thin Si-B layer as a diffusion source