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501.
Community forest management (CFM) has received increasing worldwide attention from governments, researchers and educational
institutions over the past two decades. Many governments, especially in developing countries, have prioritized CFM over traditional
forest management systems. In Thailand, CFM is not recognized by the legal system; however, there are de facto CFM practices under common property resource regimes. CFM has in essence been practiced here for hundreds of years by local
people, and represents an important aspect of Thai culture. This study aims at evaluating CFM in Thailand in the context of
sustainable development. To meet the objective, the study gathered information through focus group discussions with various
stakeholders: academics, Forest Department staff, and members of the Chang Tok Tay community forests. From the study, it emerged that forest resources are critical for the livelihoods and survival of rural
people, and so they have protected forests to ensure sustainable livelihoods. This study identified that prospects for sustainable
CFM in Thailand are bright because: (i) community members are highly motivated and are sufficiently interested to protect
trees because they are well aware that their livelihoods are under threat from depleting forests; (ii) tradition and culture
of rural people support their relation with nature; (iii) non-timber forest products (NTFPs) play a crucial role in local
livelihoods for subsistence and necessitate protection of the forest watershed, which is vital to support their occupations;
(iv) spiritual rituals such as those where Buddhist monks bind yellow cloth on trees play a vital role in protecting trees,
something rare in other countries. The study further identified various hindrances to achieve sustainable CFM: (i) legal support
for CFM is absent; (ii) the Royal Forest Department (RFD) cannot transfer appropriate technology to community people due to
lack of legal support; (iii) scope for developing effective strategies for sustainable CFM by combining traditional knowledge
with existing scientific knowledge is limited; (iv) a formal institutional arrangement for CFM does not exist; and (v) community
members’ access to the hard technology of CFM is limited. Therefore, in addition to legalizing CFM, a formal institutional
framework for elaboration, implementation and control of CFM is essential to achieve sustainable CFM in Thailand. 相似文献
502.
This study investigated the behavior of piezoelectric, dielectric, and elastic constants and the crystallinity in wood cellulose by repeated measurements (n = 42) between 100°C and 220°C. There was an insignificant change in the piezoelectric constant during repeated measurements in this temperature range. On the other hand, thermal decomposition of the amorphous region contributed to the decreasing trend of dielectric and elastic constants, although only a small increase in the elastic constant was found at the time of the initial measurements. The increase in the repeated measurements in this temperature range resulted in an increase in the piezoelectric loss modulus constantd
25, which is closely related to energy loss. Thed
25 peak shifted to a higher temperature with increasing measurements, which might be due not to the increase in rigidity of the wood specimen but to the increase in total peak area, which was observed during the later measurements. At the same time, variations of piezoelectric loss modulusd
25 ande
25 at advanced stages of the measurements suggested damage and structural changes in the wood. 相似文献
503.
We evaluated the phenology and litterfall dynamics of the mangrove Bruguiera gymnorrhiza (L.) Lamk along the Okukubi River, Okinawa Island, Japan. Over 3 years, this species showed the highest litterfall of leaves and stipules in summer and the lowest litterfall in winter. From Kendall’s coefficient of concordance, the monthly changes in leaf, stipule, and branch were strongly and significantly concordant among years. Leaf and stipule litterfall could be governed by monthly maximum wind speed, monthly day length, and monthly mean air temperature. Branch litterfall depended on monthly maximum wind speed and monthly rainfall, and increased exponentially with increasing monthly maximum wind speed. Mean total litterfall was 11.8 Mg ha?1 yr?1, with the largest component being leaf litterfall (65.8 %). Annual leaf litterfall per plot was almost constant regardless of the tree density of the plot. Mean leaf longevity was 18 months. Flower and mature propagule litterfall might be influenced by monthly mean air temperature, monthly day length and monthly mean air temperature. The average development periods from flower buds to flowers and flower buds to mature propagules were 1 and 8 months, respectively. Except for leaf and branch, all vegetative and reproductive organ litterfall had clear annual cycles. B. gymnorrhiza showed a positive correlation between leaf production and reproductive organ production. 相似文献
504.
Md. Motiur Rahman Yasushi Furukawa Isao Kawata Mohammed Mahabubur Rahman Mahbubul Alam 《Small-Scale Forestry》2005,4(3):359-376
This study examines the species composition, diversity and economic importance of homestead forests in the household economy
of central Bangladesh. The study documents 57 homestead forest species and their main usage in 90 households across three
villages of Gazipur Sadar Upazila. Homestead forests in Bangladesh comprise a mixture of fruit, timber and bamboo species.
While superficially homestead forestry appears unimportant in rural livelihoods, in reality the contribution is huge, both
as a source of food security and for other necessary household materials. A clear understanding of the physical characteristics
and economic role of homestead forests in rural livelihoods is vital for ensuring sustainable resource management. Income
and production of homestead forestry on a per hectare basis are found to vary widely between landholding size classes. Significant
relationships are identified between forest performance (production and income) and species richness and education level.
Homestead forestry appears to be a potential subsistence income generating land-use practice in the study area. The economic
scope of homestead forestry can be further enhanced provided the appropriate species composition of the forest is achieved
and the education of forest owners is ensured through targeted management and policy interventions. 相似文献
505.
This study evaluated the potential of steam pre-treatment for making highly compressed phenol-formaldehyde (PF) resin-impregnated
wood at a low pressing pressure. Sawn veneers of Japanese cedar (Cryptomeria japonica) were first subjected to saturated steam at different steaming temperatures (140°-200°C), followed by impregnation with a
20% low molecular weight PF resin aqueous solution resulting in a weight gain of around 50%-55%. Four oven-dried treated veneers
were laminated and compressed up to a pressing pressure of 1 MPa at a pressing temperature of 150°C and pressing speed of
5 mm/min, and the pressure was held for 30 min. Steam treatment, causing partial hydrolysis of hemicellulose, accelerated
the compressibility of Japanese cedar in the PF resin-swollen condition. As a consequence, a discernible increment in density
was achieved at a pressing pressure of 1 MPa due to steam pretreatment between 140° and 200°C for 10 min. It was also found
that even a short steaming time such as 2 min at 160°C is sufficient for obtaining appreciable compression of PF resin-impregnated
wood. The density, Young’s modulus, and bending strength of steam-treated (200°C for 10 min) PF resin-impregnated wood composite
reached 1.09 g/cm3, 20 GPa, and 207MPa, respectively. In contrast, the values of untreated PF resin-impregnated wood composite were 0.87 g/cm3, 13 GPa, and 170MPa, respectively. 相似文献
506.
Compressive deformation of wood impregnated with low molecular weight phenol formaldehyde (PF) resin IV: Species dependency 总被引:1,自引:0,他引:1
Flat-sawn specimens of eight wood species, albizia (Paraserianthes falkata, 0.23 g/cm3), Japanese cedar (Cryptomeria japonica, 0.31 g/cm3), red lauan (Shorea sp., 0.36 g/cm3), European spruce (Picea abies, 0.44 g/cm3), Douglas fir (Pseudotsuga douglasii, 0.50 g/cm3), elm (Ulmus sp., 0.51 g/cm3), Japanese beech (Fagus crenata, 0.64 g/cm3), and Japanese birch (Betula maximowicziana, 0.71 g/cm3), were impregnated with low molecular weight phenol-formaldehyde (PF) resin and their compressive deformations were compared.
The volume gain (VG) and weight gain due to 20% resin solution impregnation were different among species. Furthermore, the
specific volume gain (VG/specific gravity), indicating the degree of swelling of the cell wall, also varied from 17.7% for
European spruce to 26.4% for elm. Oven-dried specimens of each species were compressed using hot plates fixed to an Instron
testing machine. The deformation behavior of resin-impregnated wood up to 10MPa was significantly different among the species.
Stress development during cell wall collapse for low density wood was minimal. As a consequence, a significant increment of
density occurred up to 2MPa for low density wood such as albizia and Japanese cedar. When PF resin-impregnated wood was compressed
up to 2MPa and the pressure was kept constant for 30min, the density of Japanese cedar reached 1.18g/cm3, about 30% higher than the density of compressed Japanese birch, which possesses an original density that is 2.5 times higher
than that of Japanese cedar. The mechanical properties of resin-impregnated wood, especially low density wood, increased with
density. Hence, it is manifested that low density wood species have an advantage as raw materials for obtaining high-strength
wood at low pressing pressure. 相似文献
507.
Sileshi BELEW Jin-Yoon KIM Md.Akil HOSSAIN Ji-Yong PARK Seung-Jin LEE Yong-Soo PARK Joo-Won SUH Jong-Choon KIM Seung-Chun PARK 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(3):327-329
Pharmacokinetic (PK) parameters of marbofloxacin (MRFX) in Korean cattle, Hanwoo, were
determined following its intravenous (i.v.) or intramuscular (i.m.) administration at a
dose of 2 mg/kg. Area under the curve (AUC0–24 hr), half-life (t1/2)
and total body clearance (CLB) of i.v. MRFX were 6.87
hr∙µg/ml, 2.44 hr and 0.29 l/kg∙hr,
respectively, and the corresponding values for i.m. administration of MRFX were 5.07
hr∙µg/ml, 2.44 hr and 0.39 l/kg∙hr.
The suggested optimal doses of MRFX in Hanwoo cattle, calculated by integration of PK data
obtained in the present study and previously reported minimum inhibitory concentration
(MIC) for MRFX against susceptible (MIC ≤1 µg/ml) and
intermediate (MIC ≤2 µg/ml) pathogenic bacteria, were
2.1 and 4.2 mg/kg/day by i.v. route and 3.9 and 7.8 mg/kg/day by i.m. route. 相似文献
508.
Shoma MIKAWA Shohei YAMAMOTO Md Shafiqul ISLAM Noriyuki KAJI Takahisa MURATA Risuke MIZUNO Hiroshi OZAKI Masatoshi HORI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(10):1195-1199
Maropitant is a neurokinin 1 receptor (NK1R) antagonist that is clinically used as a new
anti-emetic drug for dogs. Substance P (SP) and its receptor NK1R are considered to
modulate gastrointestinal peristalsis. In addition, SP works as an inflammatory mediator
in gastrointestinal diseases. Aim of this study is to clarify the effects of maropitant on
intestinal motility and inflammation in mice. Ex vivo examination of
luminal pressure-induced intestinal motility of whole intestine revealed that maropitant
(0.1–10 µM) increased frequency of contraction, decreased amplitude of
contraction and totally inhibited motility index in a concentration-dependent manner. We
measured intestinal transit in vivo by measuring transportation of orally
administered luminal content labeled with phenol red. Our results demonstrated that
maropitant (10 mg/kg, SC) delayed intestinal transit. Geometric center value was
significantly decreased in maropitant-treated mice. Anti-inflammatory effects of
maropitant against leukocytes infiltration into the intestinal smooth muscle layer in
post-operative ileus (POI) model mice were measured by immunohistochemistry. In POI model
mice, a great number of CD68-positive macrophages or MPO-stained neutrophils infiltrated
into the inflamed muscle region of the intestine. However, in the maropitant treated mice,
the infiltration of leukocytes was not inhibited. The results indicated that maropitant
has ability to induce disorder of intestinal motility in mice, but has no
anti-inflammatory action in the mouse of a POI model. In conclusion, in mice, maropitant
induces disorder of intestinal motility in vivo. 相似文献
509.
Md. Sharif Hossen Itaru Sotome Kazuko Nanayama Tomoko Sasaki Hiroshi Okadome 《Cereal Chemistry》2016,93(1):53-57
The digestibility and hydration properties of wet‐ground submicron‐scale rice flour were compared with those of dry‐ground coarser microscale flours. The submicron flour (mean size 0.6 µm) was produced in a wet‐media mill with 0.3 mm zirconia beads by continuous 24 h pulverization. The solubility, water absorption index, and swelling power increased as the mean particle size decreased, reaching maximum values in the submicron flour. Starch damage was high in the submicron flour, with the absence of intact starch granules. The digestibility also increased as the particle size decreased, and it was highest in the submicron flour. These results show that wet‐ground submicron rice flour has different functional properties from dry‐ground coarser flour. The digestibility was more strongly influenced by starch damage and the water absorption index than by the mean particle size. 相似文献
510.
Tadao Wagatsuma Matsuo Uemura Wataru Mitsuhashi Masayoshi Maeshima Satoru Ishikawa Takeshi Kawamura Tetsuya Murayama Yoshihito Shiono Md. Shahadat Hossain Khan Keitarou Tawaraya 《Soil Science and Plant Nutrition》2005,51(1):135-139
It has been suggested that plasma membrane (PM) lipids play a major role in aluminum (Al) tolerance; however, no direct investigations have been carried out using PM lipids from root-tips. Here we report a new technique for PM isolation as an alternative to the laborious two-polymer phase partitioning method that is commonly applied, as follows: 1) separation of protoplasts from 1-cm root-tip portions by enzymatic digestion, 2) attachment of the purified protoplasts to glass plates coated with polylysine, 3) preparation of PM ghosts by successive burst of the attached protoplasts using three separate buffer solutions (25 mM PIPES, 5 mM EDTA, and 2 mM MgCl2 , at pH 7.0) with slow stirring for 60 s. The PMs were confirmed to be devoid of organelle membranes by fluorescence microscopy, thin layer chromatography (TLC) and western blot analysis. The PM lipids obtained were found to be useful for studies on their differential permeability and lipid composition between lines of triticale or cultivars of maize under Al stress. 相似文献