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101.
Steam distilled oil from the shoots, separated leaves, and stem, as well as from the flower of laurel (Laurus nobilis), grown in Montenegro, were analyzed by GC and GC/MS. The yield of essential oil was as follow: 1.4% in young shoots, 1.5%
in the separated leaves, and 0.7% in separated stems. The main constituents of all investigated oils were 1,8-cineole, methyleugenol,
and α-terpinyl acetate. Besides, α-pinene, β-pinene, sabinene, and linalool were also present. It was interesting and important for commercial samples of laurel essential
oil that there was no significant difference among the essential oil obtained from young shoots and those obtained from leaves
and stem. The main constituents of the flower oil were 1,8-cineole (15.7%), β-caryophyllene (9.5%), γ-muurolene (7.1%), α-terpinyl acetate (6.5%), and methyleugenol (3.9%).
Published in Khimiya Prirodnykh Soedinenii, No. 4, pp. 337–339, July–August, 2007. 相似文献
102.
以香石竹品种“媚娘”为试材,研究不同光照强度对其生长的影响,结果表明:白天提供平均光照强度为294301x的香石竹侧芽数、侧芽长度及粗壮程度、植株粗壮程度、抗倒伏能力均高于白天提供平均光照强度为151701x和78201x的香石竹。 相似文献
103.
通过对投篮过程中腕、指关节的技术分析和一系列的实验的研究,证明腕、指关节的灵活性对投篮技术有着极其重要的影响,并探索出一种可以有效提高篮球运动员腕、指关节灵活性的极为有效的训练方法. 相似文献
104.
ZiQiang Wang 《科学通报(英文版)》2012,57(10):1169-1177
Palissya,a little-known reproductive organ with a long history,is recorded from China and Asia for the first time.A new species,Palissya hunanensis(sp.nov.) ,is described from the Upper Triassic Rhaetican strata of the Zixing coal field of Hunan Province.The ovulate cone has a compound shoot system that consists of a main axis and many helically-arranged axillary structures re-ferred to as female dwarf shoots,each of which is subtended by a bract.Despite a superficial similarity,P.hunanensis differs from the typical species P.sphenolepis(Braun) Nathorst in a number of subtle but consistent features:the cone is much smaller and narrower,the bracts are much thinner,there are fewer pairs of cup-like seed scales,and the seed scales are adaxially attached to a thick axis rather than to bracts.These traits are all distinctly different from other species of the genus.Moreover,SEM obser-vation of the new species reveals morphological features of the seed scales and seeds and details of the female dwarf shoot;sig-nificantly increases our knowledge of Palissya;and provides new evidence that it is a conifer.Palissya is related to the Lower Permian Lebowskia,a voltzian conifer bearing ovuliferous structures similar to the bract plus dwarf-shoot organization of Palis-sya.Palissya-type conifers probably grew in specialized marine-continent habitats,unlike most other extant and extinct conifers that grow in drier upland environments. 相似文献
105.
绒毛白蜡营养器官中Na^+、K^+、Cl^-的分布 总被引:2,自引:0,他引:2
为研究白蜡的抗盐生理机制,对盐渍生境下1—3年生绒毛白蜡(F.velutina)不同营养器官中盐离子的分布进行了分析。研究结果显示,不同器官中Na^+、K^+和Cl^-含量存在显著差异。根系,Na^+、K^+含量最高,Na^+平均达0.72%,K^+平均达13.95%;叶片,Cl^-含量最高,平均达1.04%;Na^+、Cl^-含量均随树龄的增大而减少,K^+含量随树龄的增大而增加。结果表明绒毛白蜡的高耐盐特性受营养器官中盐离子分布规律支持,并且绒毛白蜡能够随着树龄增长,逐步适应盐渍生境,耐盐能力逐步提高。 相似文献
106.
运用文献资料法、观察法、数理统计法、归纳分析法。对在南非举行的第19届世界杯足球赛决赛阶段32支队伍64场比赛的145个进球进行分析(不包括在点球决胜期所发进的点球)。得出以下结论:抢点直接脚射是所有进球方式中运用最多的,下半时后30分钟是进球的高峰时段.在进攻前场发动进攻并进行较少次数的传球,进球凡率较大,在支持射门进球的最后一次传球的各种助攻方式中,直接传运用次数最多且效果较好。 相似文献
107.
以巨尾桉(Eucalyptus grandis×E.urophylla)广林9号幼林为材料,采用组培繁殖和扦插繁殖两种苗木进行桉树生长规律及抗病性衰退的比较研究。组培繁殖设4个处理,分别为第1、8、15、28次继代苗(简称为组培1代、组培8代、组培15代和组培28代);扦插繁殖设3个处理,种植第15代组培苗做采穗圃,分别于第1、2、3年后采穗扦插的扦插苗(简称为1年扦插、2年扦插和3年扦插)。试验结果表明,不同无性繁殖方法的幼林树高、地径生长曲线呈双峰型,峰值分别出现在3月和6月,树高、地径生长量及月增长量变化不同,组培苗在地径生长方面具有较大优势,树高生长方面虽然前期较差,但后期增长快,总体上仍具有优势;同一繁殖方法随着繁殖代数增加,树高、地径生长均呈下降趋势;不同繁殖方法以及不同繁殖代数都会对抗青枯病能力造成影响,组培苗的抗病性优于扦插苗,同一繁殖方法随着繁殖代数的增加抗病性下降,但抗病性衰退速度不同;不同无性繁殖的抗焦枯病能力不同,组培苗随着继代次数的增加而减弱,扦插苗随着繁殖年份的增加而升高;7种无性繁殖复壮措施的抗衰退能力为组培1代最强,组培8代次之,3年扦插最弱。 相似文献
108.
109.
[目的]笋用竹林经营中合理的竹林结构是保证竹林高产稳产的前提条件,本研究目的在于为优化绿竹竹林结构、进一步提高笋用竹林产量提供科学依据.[方法]以常规母竹留养方式(每年都留养竹,1年竹、2年竹数量比为3:1)为对照,对长周期母竹留养竹林(每年留养1次,4年时更换全部母竹)进行发笋能力、笋期、产量、经济效益等指标的评价.... 相似文献
110.
《印度化学会志》2022,99(12):100791
With the ongoing global demands for modern commodities, anthropogenic activities by industries and humans have brought a colossal pressure to the natural water bodies. Though numerous scientific interventions or treatment techniques have been proposed, the need for a viable low-cost method has been a quest for many researchers. Adsorption as such has been in the limelight as an effective method in recent times using various feedstock biomass waste. Our present piece of research aims to use the non-edible biomass waste generated from bamboo shoots as a sustainable low-cost biochar adsorbent and examine its efficiency in the removal of ferrous (Fe2+) ions from an aqueous solution. The batch adsorption study was conducted and the optimum dose and concentration were found to be 0.2 g and 7 mg L?1 with the Langmuir isotherm model best describing the experimental data. Furthermore, kinetic study suggests that the overall sorption rate predominantly follows the chemisorption pathway. Multiple studies suggest bamboo is an excellent adsorbent for treating various inorganic & organic contaminants; here we have highlighted the multifaceted applications of waste bamboo shoots as an effective adsorbing material. The obtained results can lead to additional benefits and usage of bamboo shoots (waste) with future research prospects. 相似文献