林业企业电网实现最佳无功补偿的技术方法

本文对林业企业电网实现最佳无功补偿问题进行了探讨,并提出了确定电网实现最佳无功补偿容量的计算公式及具体方法,为提高电网功率,缓解林区供电紧张的问题提供了依据。     

Identification of CpTI Gene Integration for 2-year-old Transgenic Poplars at DNA Level

The putative transgenic hybrid triploid poplars [(P. tomentosa P. bolleana) P. tomentosa] with CpTI gene have been outplanted in test field for 2 years. Although the authors previous studies have proved that they are highly resistant to 3 species of poplar-threatening insect pests and contain high content of CpTI protein in foliage, incorporation status of foreign CpTI gene in poplar genome is uncertain. In this present study, the incorporation of foreign CpTI gene in genome of 5 transgenic poplars was confirmed by PCR and Southern blotting analysis. DNA amplification showed that there were clear DNA bands of about 450bp specific to CpTI gene in transgenic lanes, while no corresponding band in non-transgenic lane was observed. Correspondingly, clear DNA hybridization signals and no signal were exhibited on film for DNA Southern blotting analysis in transgenic lanes and non-transgenic lane, respectively, which further confirmed the stable integration of foreign CpTI gene in genome of 2-year-old transgenic poplar.     

Caratheódory定理与热力学第二定律

在重温Caratheódory定理的基本理论结果的基础上,着重阐明了该定理的普适性,从而判明了Clausius热力学第二定律可适用的条件,以及负能态热力学存在的合理性.     

Human responses to flower fragrance of Lilium ‘Siberia’ and Rosa ‘Escimo’

The objective of our study was to lay a foundation for the effect of flower fragrance on human emotions and to provide a theory for the choice of indoor plants and the improvement of the olfactory environment. Specifically, our purpose was to study human physiological responses to flower fragrance of Lilium ‘Siberia’ and Rosa ‘Escimo’. The participants were 31 college students. Blood pressure, pulse rate, finger temperature (FT) and galvanic skin response (GSR) were measured. The results show that the fragr...     

基于DDS的宽带信号发生器

DDS(直接数字频率合成)作为一种新的频率合成技术,已经广泛应用于雷达信号的产生等领域。由于DDS采用了不同于传统频率合成方法的全数字结构,因而具备许多直接式频率合成技术和间接式频率合成技术所不具备的优点,例如具有极高的频率分辨率和极短的频率转换时间等。但是由于DDS本身固有的相位截断技术,会造成一定的杂散。因此,采用MATLAB仿真的方法对DDS的输出性能进行改善。     

小兴安岭典型泥炭沼泽土壤水分物理性质研究

对小兴安岭5类典型泥炭沼泽土壤水分物理性质进行对比研究,结果表明:落叶松-杜香-泥炭藓沼泽土壤容重最小,非毛管孔隙最高,持水性最好;漂筏苔草沼泽和油桦-笃斯越桔-修氏苔草沼泽次之,修氏苔草沼泽和白桦-油桦-小叶章沼泽相对较差.落叶松-杜香-泥炭藓沼泽0～40 cm平均土壤容重为0.06g·cm-3,非毛管孔隙31.69%,总孔隙度高迭87.19%,平均土壤质量含水量、最大持水量、毛管持水量和最小持水量分别为1130.1%、1586.57%、1007.71%和882.70%,是对照林地的56.6倍、26.4倍、24.9倍和25.5倍.在5类泥炭沼泽中,白桦-油桦-小叶章沼泽0～40 cm平均土壤容重最高(0.74 g·cm-3),总孔隙度最低(62.02%),土壤各持水指标均最小,但其持水指标均显著高于对照林地.     

余甘子对强致癌物N-亚硝基化合物在人体内合成的阻断作用

本文采用Ohshima的方法,以尿中N-亚硝基脯氨酸(NPRO)量为指标,研究了余甘子果汁阻断人体内N-亚硝基化合物(NNC)的合成。12名志愿者摄入L-脯氨酸500 mg和硝酸钠300 mg后,尿中NPRO的量平均为75.10 nmol,而当摄入上述两种药物的同时,分别给予同浓度的抗坏血酸和余甘子果汁后,尿中NPRO的含量则分别降为41.08 nmol和20.79nmol,且后者此本底值(25.55 nmol)还低。表明在本实验条件下,摄入含抗坏血酸75mg的余甘子果汁13ml,即能完全阻断500mg L-脯氨酸和300mg硝酸钠在人体内所引起的NPRO的合成。同时也证明,余甘子果汁能有效地阻断人体内NNC的合成。     

纵带球须剌蛾的生物学特性及其防治

纵带球须刺蛾是多种农林作物的害虫。在广州1年发生1～3代,以老熟幼虫在土中茧内越冬,幼虫一般为7～8龄,幼虫感染核多角体病毒后,常成为流行病,死亡率可达90%以上。进行防治试验表明,90%敌百虫晶体40000倍液、80%敌敌畏乳剂100000倍液和50%杀螟松乳剂100000倍液等,以及2.3×10~(5-7)浓度的核多角体病毒,均对幼虫有较好的毒杀效果。     

FEEDING HABITS OF HAINAN ELDI''''S DEER

Hainan eldi's deer is a precious species of deer in the tropic zone,it is regardedas the first—class animal under protection in China.Based on all-year-round observation on thedeer's feeding habit in the reserve from 1985 to 1988,we discovered that Hainan eldi’s deer is aeuryphangous herbivore.They take various herbs as their main food and have fairly strongselectivity for woody plants,especially tending to eat the tender parts of plants and some fruits andflowers.Like other species of deer,they also like to lick the alkaline soil.This paper reports the re-search and evaluation on the feeding and choosing food characteristics of Hainan eldi’s deer,and onthe palatability of the main plants in the reserve.     

AN OBSERVATION STUDY ON BIOLOGICAL CHARACTERS AND MATING BEHAVIOR OF DAHURIAN CASEBEARER(COLEOPHORA DAHURICA FLKV.)ADULTS

Through rearing tests and observations under laboratory conditions,biologicalcharacters and mating behavior of Dahurian casebearer(Coleophora dahurica Flkv.)adultswere studied in this paper.Results discovered that the time of emergense of male adultswas 24h to 36h earlier than that of female adults.The peak of sex pheromone secretion ofthe female adults appeared of 24h to 42h after the emergence.The reaction of male adultson the sex pheromone was most sensitive during 30h to 48h after emerged,so the earlieremergence of the male adults was favorable to mating.The phenomenon of repeatedmating did not exist in female adults,but the male adults could mate for several times,with maximum of 4 times.There was a definite behavioral reaction during the matingperiod of male and female adults,and the certain period of feeding and mating times couldaffect the adults longervity to a certain degree.