Aluminium and fluoride concentrations of three tea varieties growing at Lantau Island,Hong Kong

The present project aims to investigate aluminium (Al) and fluoride (F) contents in teas (Camellia sinensis (L.) O. Kuntze). Three different commercial tea varieties: Assam variety and two China sub-varieties, a large leafed variety and small leafed variety, were collected in two tea gardens of Lantau Island tea plantation of Hong Kong. In general, high concentrations of Al and F were accumulated in the mature leaves (15.3 and of 2.07 g kg^–1 respectively). Among the three varieties, the small leafed variety exhibited the highest Al and F contents followed by the large leafed variety whereas the Assam variety had the lowest Al and F concentrations in its tea bushes. Tea products from a plantation were also analysed and it was noted that black tea had higher Al and F concentrations than green tea. The amount of Al and F released into tea liquor was also tested and the results showed that higher concentrations of Al and F were released into tea liquor under repeated infusion method than continuous infusion method.     

综合地震台网络办公自动化系统

计算机与网络技术高速发展的今天，办公自动化（OA）系统现已在各行各业得到广泛应用。目前市场上的办公软件产品很多且功能强大，但由于各个行业本身的特殊性，这些系统很不适合应用于地震部门。本文研究了综合地震台如何搭建适合自己的经济、简单、实用的OA系统，为国内其他地震台实现OA作一些建设性的理论及技术参考。     

东南亚沿海生态旅游的趋势

当地居民的生活需求、保护生物多样性的必要性和娱乐旅游使得东南亚海岸资源压力不断增 加 .在这种情况下 , 沿海生态旅游会扮演越来越重要的角色 .这篇文章考察了泰国、菲律宾、 印度尼西亚、马来西亚和越南的沿海生态旅游的开发 .     

Effects of anoxia on the activities of pyruvate kinase and phosphoenolpyruvate carboxykinase,and the production of lactate and succinate in the intertidal pulmonate Onchidium tumidium

Onchidium tumidium, an intertidal pulmonate, has evolved to depend mainly on the formation of succinate, rather than lactate and opines, to survive in anoxia. For our study O. tumidum were collected from the mud flats of the mangrove swamp at Mandai, Singapore between 1988 and 1991. After 24 h of anoxic exposure, the lactate and succinate contents of the anoxic individuals were approximately 10 and 150 times, respectively, the corresponding values of the normoxic individuals. Alanine and acetate accumulations also occurred during anoxia, though to a much lesser extent. No propionate or octopine was detected. The depletion in aspartate content in O. tumidium could not account for the amount of succinate accumulated during anoxia. The succinate formed might have originated from glycogen involving the flow of carbon through the phosphoenolpyruvate (PEP) branch point of glycolysis. In support of such a hypothesis, results indicate that there was a decrease in the affinity of pyruvate kinase from O. tumidium exposed to 24h of anoxia to PEP to facilitate succinate formation through phosphoenolpyruvate carboxykinase (PEPCK). In comparison, the affinity of PEPCK from O. tumidium exposed to anoxia to PEP was apparently unaltered.     

渗滤湿地系统的工艺设计

本研究是以占地6公顷,日处理污水1400m~3的渗滤型芦苇湿地实验工程为依托,采用静态模拟与工程运转相结合的方法,着重对污水湿地处理系统BOD_5的生物降解模型进行研究,建立了确定Q值和K_T值的方法,提出了适于天津渗滤湿地系统的Q值和K_T值,为湿地系统设计提供了重要的科学依据.     

珠江河口区翡翠贻贝中有机氯农药和多氯联苯含量及分布

对分布于珠江河口区海域的翡翠贻贝有机氯农药和多氯联苯的含量进行测定 ,结果显示 :HCHs为ND— 1.1ng·g-1,DDTs为 9.5— 191ng·g-1,PCBs为 82 .8— 6 15 .1ng·g-1.尖沙嘴码头 (维多利亚港 )贻贝积累的PCBs浓度最高 ,珠江河口桂山岛和外伶仃岛的贻贝积累的DDTs和PCBs浓度较高 ,而荷包岛 (珠江河口西海区 )的贻贝则检出含量较高的HCHs和DDTs .贻贝选择性积累含 5— 6个氯原子数的PCB异构体 .各采样点贻贝积累的PCBs组成分析表明珠江河口区海域存在两个PCBs污染源     

A novel respirometer for biological toxicity tests

ＡｎｏｖｅｌｒｅｓｐｉｒｏｍｅｔｅｒｆｏｒｂｉｏｌｏｇｉｃａｌｔｏｘｉｃｉｔｙｔｅｓｔｓＺｈａｎｇＭｉｎｑｕａｎ，ＣｈｅｎＨｕａｎｑｉｎＣｈｅｍｉｃａｌＥｎｇｉｎｅｅｒｉｎｇＲｅｓｅａｒｃｈＩｎｓｔｉｔｕｔｅ，ＳｏｕｔｈＣｈｉｎａＵｎｉｖｅｒｓｉｔ...     

长江,嘉陵江重庆段水污染控制规划

根据水质预测结果用组合规划的方法对长江，嘉陵江重庆干流段和城区段的水污染控制提出了多个不同的方案，并对各方案进行了比较，从水质，经费和施工的可行性３个方面综合评定，筛选出优先考虑方案，同时对方案实施后的效益作出了简要的叙述。     

人工污水中的N在模拟秋茄湿地系统中的分配循环及其净化效果

在温室中建立模拟红树林植物秋茄湿地系统，系统包括１年生秋茄苗、底泥和潮汐海水，分别用正常、５倍和１０倍浓度的人工制备的城市污水每周定时、定时对模拟系统污灌２次，持续１年。用以研究营养污物Ｎ在系统中的分配循环及被净化的效果。结果表明，加入系统中的污水Ｎ主要留存在土壤中，留存在植物中只有一小部分，４个处理污水浓度组植株中Ｎ元素周转期衣次为４．１年、４．９年、５．３年和４．３年，比２０龄的秋茄群落Ｎ周期     

Use of cattails in treating wastewater from a Pb/Zn mine

This article describes the use of a combined treatment system, which includes an aquatic treatment pond withTypha latifolia Linn. (Typhaceae) as the dominant species and a stabilization pond, to treat the wastewater from a Pn/Zn mine at Shaoguan, Guangdong Province, China. In 1983, it was noted thatT. latifolia bloomed in areas affected by the wastewater emitted from the mine, hence a combined purification system was subsequently built. The influent contained high levels of total suspended solids (4635 mg/liter), chemical oxygen demand (14.5 mg/liter) as well as Pb (1.6 mg/liter) and Zn (1.9 mg/liter). The results of the effluent after treatment showed that the total suspended solids, chemical oxygen demand, Pb, and Zn had been reduced by 99%, 55%, 95%, and 80% respectively. The results of plant tissue analysis indicled thatT. latifolia assimilated significant amounts of Pb and Zn, especially in the root portion. During 1986 several species of algae and fish were present in the pond, usually with a higher density in areas containing lower metal concentrations in the water. Paper was presented in part at the conference “The Use of Constructed Wetlands in Water Pollution Control” held 24–28 September 1990, Cambridge, UK.