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941.
Rohny Setiawan Maail Kenji Umemura Hideo Aizawa Shuichi Kawai 《Journal of Wood Science》2011,57(4):302-307
This study examined the effects of supercritical CO2 treatment on the curing and degradation of cementbonded particleboard (CBP). Significant correlations were found between
the supercritical CO2 treatment and mechanical properties during both curing and degradation processes. Internal bond (IB) strength, modulus of
rupture (MOR), and modulus of elasticity (MOE) values of CBP achieved their maximums by supercritical CO2 treatment in 30 min. These conditions indicated that supercritical CO2 treatment accelerates the curing process rapidly and enhances the mechanical properties of the CBP. However, these values
decreased in treatment from 60 min to 10 days and had a negative effect on board performance, indicating that supercritical
CO2 treatment over a longer time span leads to degradation of the CBP. Furthermore, X-ray diffractometry (XRD), thermal gravimetry
(TG-DTG), and scanning electron microscopy (SEM) observation clarified that the mechanisms of degradation are directly affected
by the mineralogical composition of the system, in par ticular, by the calcium carbonate content as caused by carbonation. 相似文献
942.
943.
944.
José Climent Maria Regina Chambel Marta Pardos Francisco Lario Pedro Villar-Salvador 《European Journal of Forest Research》2011,130(5):841-850
Rooting space is considered as a resource in plants, but comparative studies on the biomass allocation plasticity in response
to rooting volume (RV) are rare. We compared responses in growth, biomass allocation and ontogenetic heteroblasty in nine
hard pine species of contrasted ecology. Seedlings were cultivated in containers of 0.2, 0.5, 1.0, 2.8 and 7 L for two growing
seasons (425 days). Reduction in RV caused a reduction in plant absolute and relative growth rate and biomass allocated to
stems but it increased biomass allocated to roots. RV affected to a lesser extent and in a less consistent direction allocation
to leaves. Species that grew faster (higher relative growth rate) had a steeper decrease in growth with the reduction in RV.
Ontogenetic heteroblasty, evaluated as the proportion of secondary needles in the needle biomass, showed highly different
plasticity patterns in response to RV. Decrease in RV caused negligible or no change either in the most ontogenetically delayed
Mediterranean pines or in the most ontogenetically advanced pines, the mesic Pinus sylvestris and P. uncinata. By contrast, ontogenetically intermediate species showed steep reaction norms in response to reduction in RV. While P. pinaster and P. brutia showed marked rejuvenation, P. nigra accelerated the development of adult foliage. 相似文献
945.
Mikko Mönkkönen Pasi Reunanen Janne S. Kotiaho Artti Juutinen Olli-Pekka Tikkanen Jari Kouki 《European Journal of Forest Research》2011,130(5):717-727
Setting aside parcels of land is the main conservation strategy to reduce the rate of biodiversity loss worldwide. Because
funding for biological conservation is limited, it is important to distinguish the most efficient ways to use it. Here, we
assess implications of alternative measures to conserve biodiversity in managed boreal forest landscapes. We calculated four
alternative spatio-temporal scenarios and compared these to the current management regime over 100-year time period. In the
alternative scenarios, a fixed amount of funding was invested in (1) permanent large reserves (each tens of ha in size), (2)
permanent small reserves (each a few ha in size), (3) temporary small reserves (based on 10-year contracts with private land
owners), and (4) green-tree retention (small groups of trees retained on clear-cuts). To assess biodiversity implications,
we used habitat suitability indices to calculate overall habitat availability for five groups of red-listed and habitat-specific
species associated with decaying spruce logs. The possibilities for timber harvests did not differ among the scenarios, but
biodiversity performance was different. The scenarios with permanent reserves tended to outperform other scenarios, suggesting
that conservation policies based on permanent reserves are the most cost-efficient in the long term. Results, however, varied
among time scales and species groups. In the short term, a strategy of investment in temporary small reserves was the most
efficient. Habitat for species associated with old spruce dead-wood and preferring shade was rare throughout all simulations,
and therefore, it is likely that these species cannot be sustained in managed forests. Species that live on fresh dead-wood
and are associated with forest edges coped well in all scenarios suggesting that such species will persist in managed landscapes
without additional conservation efforts. Explicit definition of conservation objectives and time frames for conservation action
are thus prerequisites for successful conservation planning. 相似文献
946.
947.
Background
There is an increasing demand for renewable resources to replace fossil fuels. However, different applications such as the production of secondary biofuels or combustion for energy production require different wood properties. Therefore, high-throughput methods are needed for rapid screening of wood in large scale samples, e.g., to evaluate the outcome of tree breeding or genetic engineering. In this study, we investigated the intra-specific variability of lignin and energy contents in extractive-free wood of hybrid poplar progenies (Populus trichocarpa × deltoides) and tested if the range was sufficient for the development of quantitative prediction models based on Fourier transform infrared spectroscopy (FTIR). Since lignin is a major energy-bearing compound, we expected that the energy content of wood would be positively correlated with the lignin content. 相似文献948.
FlordeFátima Rosas-Cárdenas Noé Durán-Figueroa Jean-Philippe Vielle-Calzada Andrés Cruz-Hernández Nayelli Marsch-Martínez Stefan de Folter 《Plant methods》2011,7(1):4
Background
Small RNAs emerged over the last decade as key regulators in diverse biological processes in eukaryotic organisms. To identify and study small RNAs, good and efficient protocols are necessary to isolate them, which sometimes may be challenging due to the composition of specific tissues of certain plant species. Here we describe a simple and efficient method to isolate small RNAs from different plant species. 相似文献949.
Penultimate and last instar larvae of the common citrus swallowtail butterfly, Papilio demoleus L. (Papilionidae: Lepidoptera), were treated with different doses of a novel juvenoid, diofenolan. Several deformities were
observed as a result of topical administration of diofenolan which include delay in larval–larval and larval–pupal ecdysis,
ecdysial failure, mortality, severe reduction in pupation, deformed pupae and complete inhibition of adult emergence. The
juvenoid diofenolan severely hampers the normal growth, development and metamorphosis of P. demoleus and can be incorporated into integrated pest management programs for successful control of this important pest of citrus
all over the world. 相似文献
950.
Alate viviparous females of Wahlgreniella nervata (Gillette) were found on a Damask rose (Rosa damascena Mill.) plantation in Isparta Province, Turkey. The aphid is recorded for the first time from Turkey. Besides, Damask rose
is a new host for this species. Brief information about this aphid including a key to the alate females of aphid species known
to infest Damask rose in Turkey is provided. 相似文献