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51.
赤潮防治剂对中国对虾的毒性研究   总被引:1,自引:0,他引:1  
为研究赤潮防治剂对中国对虾的影响,进行了粘土、Ca(CIO)2、AICI3、FeCI3对中国对虾的毒性实验。结果表明:(1)粘土对对虾基本无毒性;(2)Ca(CIO)2在低浓度下对对虾无毒,在高浓度下对对虾有急性和慢性毒性;(3)AICI3和FeCI3在对虾体内有一定的积累,但其毒性效应有待于进一步分析。  相似文献   
52.
IntroductionHeavymetalsleadtolong termcontaminationofenvironmentsincetheycannotbechemicallydegradedandhavelowproportionofsolublespeciation .Itiswelldocumentedthatchelatingagentsareabletodislodgeadsorbedheavymetals,leadingtoincreaseintheirsolubilityandb…  相似文献   
53.
简在友  许桂芳  孟丽 《生态环境》2007,16(1):201-204
微量元素对植物的生长发育有着十分重要的意义。对太行山野生红豆杉(Taxus chinensis var.mairei)菌根菌菌丝在分别加有硫酸锌、钼酸铵以及硫酸亚铁的PDA培养基中的生长发育状况进行了试验研究。所得数据同PDA对照组进行比较分析后,结果表明:Mo元素对红豆杉菌根菌菌丝的生长发育有很好的促进作用;Fe元素明显地促进红豆杉菌根菌菌丝的生长发育;Zn元素在一定范围内对红豆杉菌根菌菌丝的生长发育有一定的抑制作用。实验结果揭示出红豆杉菌根菌生长发育的一些营养因素。  相似文献   
54.
脂肪酸延长酶1(FAE1)是广泛存在于植物中并定位于内质网上的一种能催化脂肪酸碳链延长的酮脂酰CoA合成酶.根据Genbank上已知的植物FAE1基因设计引物,以从甘蓝型油菜叶片中提取的总DNA为模板,进行PCR扩增,获得了1380bp的片段.回收该片段,并连接到pMD18-T载体测序.序列比对结果说明了该片段与植物中已知的FAE1序列有极高的相似性,并且不存在内含子序列.将该片段通过高保真酶扩增,EcoRⅠ酶切消化后定向克隆到pGEX-2T表达载体中,在IPTG诱导下于28℃表达出Mr76×103的蛋白质条带.用兔抗GST多克隆抗体做第一抗体进行Western-blot检测,并获得阳性检测结果.这为甘蓝型油菜脂肪酸链延长酶基因FAE1功能的进一步研究奠定了基础.图4表1参14  相似文献   
55.
Germplasm collection is important to preserve and maximize genetic diversity for germplasm conservation. Tsuga dumosa ( D. Don) Eichler in Engler & Prantl. and T. chinensis var. forrestii (Downie) Silba germplasm was collected from three localities in China: Mt. Yulong, Wenfeng Temple and Mt. Dishiergu, Yunnan Province. Accessions were identified based on morphological characters and RAPD markers. The shapes of the apices and margins of needles were examined, and the length and width of needles, cones and seeds from accessions of mature plants were used to compare the morphological differences and to identify the germplasm. Molecular markers generated by randomly amplified polymorphic DNA (RAPD) were also used to characterize the taxa. Although the clustering based on RAPD markers was inconsistent with the morphological characters of the needles, based on the overall morphological characters and on RAPD markers, the accessions from Mt. Yulong and Wenfeng Temple were identified as T. chinertsis var. forrestii, and those from Mt. Dishiergu identified as T. dumosa. Taxonomic identification of the accessions was made based on morphology and by RAPD markers concurred. The results indicate that the shapes of the apices and margins of needles particularly from young plants could not be used as a possible key to identify T. dumosa and T. chinertsis var. forrestii. Fig 6, Tab 3, Ref24  相似文献   
56.
荔枝花发育过程中雌雄蕊内源激素的动态变化   总被引:10,自引:0,他引:10  
分析了荔枝花性别决定中雄蕊和雌蕊内源激素含量的动态变化 .结果发现 :雌蕊的发育与较高浓度的IAA和iPAs相关联 ;GA和ZRs的含量在较低浓度时有利于性器官发育 ,而较高浓度则抑制了对应性器官的发育 ;在败育的雄蕊或雌蕊中都含有较高浓度的ABA ,但从激素平衡的角度分析 ,促进生长物质与抑制生长物质的比值相对高时 ,即雄蕊的ABA浓度相对较低 ,雄蕊发育正常 ;当该比值相对较低时 ,即雌蕊的ABA浓度相对较高 ,雌蕊发育正常 .提出调节荔枝雌、雄花的发育不是某一种激素单独作用的结果 ,而是各种激素在时间、空间上的相互作用产生的综合效果 .图 2表 2参 17  相似文献   
57.
施用中量微量元素对小白菜产量和硝酸盐含量的影响   总被引:3,自引:3,他引:3  
为研究降低蔬菜硝酸含量的施肥技术,在不同质地的土壤上设置田间试验,对小白菜施用不同的中量和微量元素。结果表明,小白菜对施用的各种中量、微量元素在不同质地的土壤上有不同的响应;在合理施氮、磷、钾肥的基础上,有选择性地适量施用中量、微量元素,不仅可提高蔬菜的产量,而且可降低其体内硝酸盐的含量。  相似文献   
58.
Summary. Larvae of the turnip sawfly, Athalia rosae L. (Hymenoptera: Tenthredinidae), sequester glucosinolates of their host plants, namely members of the Brassicaceae family, in their haemolymph. Therefore, they need to circumvent myrosinase activities of the plant tissue which normally hydrolyse the glucosinolates after plant damage. Effects of varying levels of glucosinolates and myrosinases on the performance of A. rosae were investigated using homozygous lines of Brassica juncea (L.) with either (1) low glucosinolate (lowGS) and low myrosinase (lowMR), (2) high glucosinolate (highGS) and high myrosinase (highMR), or (3) high glucosinolate (highGS) and low myrosinase (lowMR) levels. To insure that the given quantities remained as constant as possible, newly hatched larvae were enclosed on the second-youngest leaf of a plant, and were offered a new plant of comparable physiological age (6-leaf-stage) every day. The performance of A. rosae was little affected by leaf quality. Body masses of eonymphs and adults were on average lowest on the highGS/highMR-line, but these differences were rarely significant. The pupal developmental times of females and males were longest on the highGS/lowMR-line in only one of two replicate experiments. All other performance traits (developmental times of larvae, egg numbers, adult longevity) were not significantly different. Glucosinolates, sequestered by the larvae, are carried through the pupal stage. The glucosinolate concentration measured in adult insects reflected the level of the host plant line, without showing any obvious costs for sequestration. Obviously, A. rosae is highly tolerant to variation in the glucosinolate-myrosinase system of its host. In addition, induced changes of glucosinolate concentrations and myrosinase activities caused by 24 h-feeding of groups of three small larvae were analysed in the second-youngest leaves. In contrast to the patterns most herbivores evoke on Brassicaceae, namely an increase of both glucosinolate concentration and myrosinase activity, we detected a significant decrease of both traits in all three lines where the respective trait was originally high in the plants. Although glucosinolate levels dropped in the highGS lines about 50%, these still contained higher concentrations than the lowGS line. Whereas the activity of soluble myrosinases remained highest in the highMR line, even after a decrease to almost 30% due to feeding, the levels of insoluble myrosinases converged after feeding in lowMR and highMR lines. Levels of the signalling molecule salicylic acid slightly decreased on average after feeding, whereas jasmonic acid was below the detection threshold in almost all samples. The concentration of several molecules varies strongly in plant tissue with age and can change due to induction by herbivore feeding. Therefore, if performance of an insect species is measured on plants with specific traits, the variability in these traits needs to be carefully controlled in experiments.  相似文献   
59.
磷、锌和镉交互作用对小白菜生长和锌镉累积的影响   总被引:1,自引:0,他引:1  
帅祖苹  刘汉燚  崔浩  魏世强 《环境科学》2022,43(11):5234-5243
利用不同元素之间的交互作用是控制作物重金属积累的有效手段.采用交替固定两因子的单一因子水平设计,以中性紫色土为材料,进行盆栽试验,探讨磷(P)、锌(Zn)和镉(Cd)不同水平组合对小白菜生长、抗氧化酶活性和Zn、Cd积累的效应和机制,为Cd污染土壤中蔬菜安全生产提供依据.结果表明,适量P和Zn的添加均能促进小白菜生长、抑制Cd在小白菜中的累积,但两者作用机制不同:P主要通过降低土壤中Cd的有效性和提高小白菜抗逆性减少小白菜对Cd的吸收,而Zn主要通过促进作物生长的稀释作用和植物体内生理拮抗作用抑制小白菜Cd的累积;外源添加1 mg ·kg-1 Cd胁迫时,小白菜抗氧化胁迫能力受到显著抑制,过氧化氢酶(CAT)和过氧化物酶(POD)活性下降,丙二醛(MDA)大量积累;P和Zn均可提高CAT活性而提高小白菜抗氧化胁迫能力,缓解Cd毒害,而对POD活性影响不大;外源添加P和Zn与Cd胁迫含量比ω(Cd):ω(Zn):ω(P)为1 :10 :200时,小白菜产量最大(55.72 g ·pot-1),且可食部Cd含量低于国家绿叶蔬菜中Cd限量50 μg ·kg-1的标准要求(GB 2762-2017);增加P和Zn占比,Cd积累量进一步下降,但小白菜产量降低.因此适当施用P和Zn肥可降Cd并增产,实现蔬菜的安全生产.  相似文献   
60.
为了探讨不同品种的油菜(Brassica napus L.)配施螯合剂对铅(Pb)污染土壤的修复效果,采用盆栽试验的方式,研究了甘蓝型油菜品种秦油1号(QY-1)和白菜型油菜品种三月黄(SYH)在0%、 2%和4%的水溶性壳聚糖(WSC)处理下对中国北方河南和南方广西两种典型Pb污染农田土壤中Pb吸收和转运的影响,并进一步在河南某Pb污染农田通过田间小区试验比较了两个油菜品种在WSC条件下的修复效率和经济效益.结果表明,盆栽条件下,与对照处理相比,QY-1和SYH的生物量受WSC含量和土壤类型影响显著,随着WSC含量增加QY-1的生物量在两种土壤条件下呈下降趋势,而低含量WSC处理下SYH生物量显著提高,在高含量WSC处理下生物量下降.如广西Pb污染土壤上2%WSC处理下SYH生物量上升最明显,与对照处理相比,生物量提高了80.96%.两个油菜品种不同部位Pb含量也受WSC含量和土壤类型的影响,QY-1地上部分和根部分在河南Pb污染土壤上随WSC含量的升高而增加,在广西Pb污染土壤上随WSC含量的升高而降低.Pb提取量是评价植物修复效率的关键.盆栽和田间试验结果表明,SYH配施WSC处...  相似文献   
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