沉淀混凝法处理含硫气田水

本文介绍用沉淀混凝法处理含硫气田水的室内试验及现场试验情况。用三氯化铁、聚合氯化铝及ＳＷ－Ⅰ处理含硫气田水，能有效地去除硫化物，而且处理后水不会因三氯化铁过量而发黄。该方法的特点是工艺简单，处理效果显著，能很好地解决含硫污水的污染问题。     

Soil water characteristics in mountain poplar stand and its benefits to soil and water conservation in loess hilly region

ＳｏｉｌｗａｔｅｒｃｈａｒａｃｔｅｒｉｓｔｉｃｓｉｎｍｏｕｎｔａｉｎｐｏｐｌａｒｓｔａｎｄａｎｄｉｔｓｂｅｎｅｆｉｔｓｔｏｓｏｉｌａｎｄｗａｔｅｒｃｏｎｓｅｒｖａｔｉｏｎｉｎｌｏｅｓｓｈｉｌｌｙｒｅｇｉｏｎＷｕＱｉｎｘｉａｏ；ＬｉｕＸｉａｎｇｄｏｎｇ...     

阳离子絮凝剂研制

介绍了一种阳离子絮凝剂的研制情况。用该絮凝剂对几种污水进行混凝处理，加药后生成的絮体大，沉降速度快，处理后水清澈度高。同时，用日立Ｈ－３００扫描电镜对絮体形态进行了观察，对阳离子絮凝剂的作用机理进行了初步探讨。     

Mating System and Sexual Selection in the Scorpionfly Panorpa vulgaris (Mecoptera: Panorpidae)

Panorpa vulgaris   has become a model insect for testing theories of sexual selection. This contribution summarizes that which has been learned in recent years and presents new data that clearly show that the mating system of P. vulgaris is not simply a resource-defense polygyny, as has previously been thought. In P. vulgaris neither the pattern in food exploitation nor the ratio of variance in the lifetime reproductive success of the two sexes is in accordance with that expected in resource defense polygynous mating systems. Lifetime mating duration is the most important proximate determinant of male fitness. Males employing alternative mating tactics obtain copulations of varying duration in relation to the following sequence: saliva secretion  1  food offering  1  no gift. The number of salivary masses which males provide to females during their lifetime is significantly correlated with the lifetime condition index. The condition index depends on the fighting prowess of males and their ability to find food items. Thus saliva secretion of Panorpa is considered a Zahavian handicap, which can serve as an honest quality indicator used by mating females. Our results confirm four main predictions of the indicator model of the theory of sexual selection: (a) the indicator signals high ecological quality of its bearer, (b) the indicator value increases with phenotypic quality, (c) the indicator value is positively correlated with the genetic quality affecting offspring fitness in a natural selection context, and (d) the quality indicator is more costly for low- than for high-quality individuals. The evolutionary consequences of the mating pattern and the sperm competition mechanism in P. vulgaris are discussed in the context the way in which sexual selection creates and maintains sperm mixing and the evolution of a promiscuous mating system.     

水泥负载TiO2光催化降解染料水溶液的研究

研究了以ＴｉＯ２为催化剂，且将ＴｉＯ２涂布在模拟工业水处理浅池的水泥质池底表面，以直管高压汞灯为光源，对有机染料酸性玫瑰红Ｂ和晒化绿Ｂ进行光催化降解的可行性。结果表明，在实验条件下，本系统对以上染料有显著的光降解作用，浓度为２５ｍｇ／Ｌ的上述二种染料溶液，经３０ｍｉｎ光照，其降解率分别达８８．２％，此外，还探讨了染料浓度，染料体积、染料溶液ＰＨ值等因素对光降解的影响。     

光催化降解有机磷农药废水的可行性

在ＴｉＯ２粉末的存在下，研究光催化降解有机磷农药废水的可行性。结果表明，ＣＯＤｃｒ６５０ｍｇ／Ｌ，有机磷１９．８ｍｇ／Ｌ的有机磷农药废水在３７５Ｗ中压汞灯照射４ｈ，ＣＯＤ去除率为９０％，有机磷将完全转化为无机磷。同时还研究了光催化剂ＴｉＯ２的用量，反应液初始ｐＨ值，空气流量，外加Ｆｅ３＋浓度等多种因素对光降解的影响；并利用太阳聚光做了室外实验     

Serum PAPP-A measurements in first-trimester screening for Down syndrome

Serum PAPP-A measurements taken from 254 women in the first trimester are reported. Eleven chromosomal abnormalities were detected. The mean serum PAPP-A levels in cases of Down syndrome were 0.44 MOM at 9 weeks gestation, 0.15 MOM at 10 weeks, and 0.29 MOM at 11 weeks. The PAPP-A level at 10 weeks was below those of pregnancies which aborted spontaneously. At 11 weeks, the pregnancies with Down syndrome recorded the lowest PAPP-A levels at that gestation. On this small sample, offering chorionic villus sampling to women with singleton pregnancies and a PAPP-A level below 0.3 MOM (approximately 6.5 per cent of this at-risk group) would have detected all the Down syndrome fetuses at 10 weeks and 50 per cent at 11 weeks without selecting those cases destined to abort. This suggests that serum PAPP-A should continue to be investigated as a potential first-trimester screening test for Down syndrome.     

毛细管色谱-多离子检测质谱法测定土壤中2,3,7,8-四氯二苯并二噁(2,3,7,8-TCDD)

环境中的多氯二苯并二(口恶)(口英)(PCDD_s)和多氯二苯并呋喃(PCDF_s)是当今最受重视的污染物之一,其中PCDD_s有75个异构体而PCDF_s有135个异构体,它们的毒性大小显著地依赖于氯原子的取代数和取代位置,由于这类污染物的低溶解度和高的辛醇/水分配系数,主要分布在土壤(85％)和沉积物(14％)中,只有1％进入空气、水和生物体.在自然环境中这类污染物代谢降解速度缓慢,从而增加了环境污染的复杂性.而鉴别这类污染物就成为一个主要研究课题.