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121.
José A. Román-Brito Edith Agama-Acevedo Guadalupe Méndez-Montealvo Luis A. Bello-Pérez 《Cereal Chemistry》2007,84(5):502-505
Nixtamalized corn flour for tortilla preparation had added xanthan gum at different concentrations. Rollability, puncture, and extensibility tests using a texture analyzer machine measured the effect of xanthan gum on the staling of corn tortillas. Rollability, puncture, and extensibility tests were simple, fast, and repeatable. The rollability parameters showed that the addition of gum produced more flexible tortillas with decreased staling. The addition of hydrocolloid decreased the force required to penetrate the tortilla, but this parameter was slightly increased when storage time increased. The parameters determined in the extensibility test showed textural differences because the fresh tortillas had a higher distance of extensibility and this parameter decreased when storage time increased. Untreated stored tortillas presented a higher modulus of deformation, work, and rupture force values. However, the addition of xanthan gum decreased these values. The addition of hydrocolloid to tortilla decreased the hardness and increased the flexibility and rubbery characteristics of tortillas. 相似文献
122.
Juan Carlos Martínez-González Francisco Javier García-Esquivel Gaspar Manuel Parra-Bracamonte Héctor Castillo-Juárez Eugenia Guadalupe Cienfuegos-Rivas 《Tropical animal health and production》2010,42(5):887-892
The aim of this study was to estimate genetic parameters for growth traits in Mexican Nellore cattle. A univariate animal
model was used to estimate (co)variance components and genetic parameters. The traits evaluated were birth weight (BW), weaning
weight (WW), and yearling weight (YW). Models used included the fixed effects of contemporary groups (herd, sex, year, and
season of birth) and age of dam (linear and quadratic) as a covariate. They also included the animal, dam, and residual as
random effects. Phenotypic means (SD) for BW, WW, and YW were 31.4 (1.6), 175 (32), and 333 (70) kg, respectively. Direct
heritability, maternal heritability, and the genetic correlation between additive direct and maternal effects were 0.59, 0.17,
and −0.90 for BW; 0.29, 0.17, and −0.90 for WW; and 0.24, 0.15, and −0.86 for YW, respectively. The results showed moderate
direct and maternal heritabilities for the studied traits. The genetic correlations between direct and maternal effects were
negative and high for all the traits indicating important tradeoffs between direct and maternal effects. There are significant
possibilities for genetic progress for the growth traits studied if they are included in a breeding program considering these
associations. 相似文献
123.
124.
Batista Pereira LG Petacci F Fernandes JB Corrêa AG Vieira PC da Silva MF Malaspina O 《Pest management science》2002,58(5):503-507
Astilbin was isolated in high yield from Dimorphandra mollis, and its insecticidal and growth inhibiting activity by stomach ingestion were evaluated against Anticarsia gemmatalis and Spodoptera frugiperda. The insecticidal activity of astilbin, the weight reduction of the larval phase and the prolongation of the larval and pupal phases were verified for both species. Astilbin was identified on the base of its NMR, MS and physical data. 相似文献
125.
Williams-Linera Guadalupe Berry Z. Carter Díaz-Toribio Milton H. Espejel-Ontiveros Ximena 《New Forests》2022,53(3):571-585
New Forests - Eriobotrya japonica is a non-native tree expanding in secondary forests and threatening the tropical montane cloud forest of central Veracruz, Mexico. Our objective was to investigate... 相似文献
126.
Fagus grandifolia var. mexicana (Mexican beech) is limited to about 10 populations (2-35 ha) in the Sierra Madre Oriental, Mexico. The objectives were to assess the current status and distribution of beech by surveying five sites. Species richness varied between three to 27 tree species in the canopy, and from nine to 29 species in the understorey. Basal area of trees?5 cm dbh varied between 27.87 and 70.98 m2 ha−1, and density from 370 to 1290 individual ha−1. Beech represented 22-99.6% of total basal area, and 6.8-83.3% of total density. Beech dominance varied from monodominant to codominance with Carpinus caroliniana, Quercus spp., Liquidambar styraciflua, Magnolia schiedeana, and Podocarpus spp. Beech total population size ranged from 180 to 6300 trees with a total of less than 1300 individuals in four sites. Anthropogenic disturbance remains a major threat to these forests. It is uncertain whether Mexican beech will be able to survive without conservation efforts. 相似文献
127.
Rosario?IturbeEmail author Carlos?Flores Claudia?Chavez Guadalupe?Bautista Luis?G.?Torres 《Journal of Soils and Sediments》2004,4(2):115-122
Background, Aims and Scope An out-of-service oil distribution and storage station (ODSS), which operated from 1966 to 2000 in Mexico, is contaminated
mainly by gasoline and diesel, showing the presence of methyl-tert-butyl-ether, benzene, toluene, ethyl benzene, and xylenes.
Nine of the 16 polycyclic aromatic hydrocarbons were found, as well as Fe, Pb, V, and Zn. The health risk assessment suggested
the necessity of reducing of three PAHs [benzo(a)anthracene, benzo(a)pyrene, and benzo-(b)fluoranthene], and vanadium. The
aim of this work is to show that soil washing (on-site) and biopiles are excellent remediation methodologies to treat soils
contaminated with petroleum derivates and metals. Applying them, it is possible to reach the goal value of 2,000 mg TPH/kg
in a few months, as requested by Mexican legislation.
Methods More than 140 m3 were excavated from the ODSS. Three soil-washing dishes were built. 1540 m3 were treated by soil washing using a nonionic surfactant. A 100 m3 biopile was built to study the system capabilities in the biodegradation of around 4,500 mg/kg of TPH using the autochthonous
microflora.
Results and Discussion The soil washing, average TPH-removal value was 83%, but values up to ca. 93% were observed. Removal values resulted in a
function of the TPH initial values. Biopile (100 m3) worked during 66 days, reaching a TPH-removal value of 85%. At the end of the processes, no PAHs were detected. The contaminated
soil was treated successfully, reaching the legislation limits (TPH values under 2,000 mg/kg, and a significant reduction
in PAH concentrations).
Conclusion and Recommendation Both systems are suitable for remediation purposes, achieving high removal efficiencies at short and medium stages. It is
highly recommended to proceed with soil washing studies, identifying new products, and mixtures, which could reduce costs
and assure optimum operation. 相似文献
128.
Arlene Wolzak Dr. Ricardo Bressani Roberto Gomez Brenes 《Plant foods for human nutrition (Dordrecht, Netherlands)》1981,31(1):31-43
Research was performed to determine the suitability of the rapid multienzymatic assay for in vitro protein digestibility estimation by using a group of native and thermally processed vegetable proteins which constitute the staple foods in developing countries. The in vitro digestibility was assessed by measuring the extent to which the pH of the protein suspension dropped when treated with a multienzyme system consisting of trypsin, chymotrypsin, and peptidase for 10 min, andStreptomyces griseus protease for 10 min more. The best correlation occurred between in vivo rat protein digestibility and the pH of the protein suspension after 15 min enzymatic treatment. The response of different types of proteins to the multienzyme assay was different, and thus distinct equations were derived for the in vitro digestibility estimation of the samples assayed. The first group included nonprocessed cereal grains and oilseeds, and cereal grain-leguminous seed mixtures. The second group was formed by leguminous seeds, and the third by thermally processed cereal and oilseed products. Although highly significant correlations between in vivo and in vitro estimates for the three groups were found, important differences occurred in the group of processed samples; therefore, more research is required with these types of samples. 相似文献
129.
Lorena A. Berruezo Guadalupe E. Mercado Cárdenas Eleonora del M. Harries Sebastián A. Stenglein Ramiro N. Curti Marcela S. Rodriguero Marta Z. Galván 《European journal of plant pathology / European Foundation for Plant Pathology》2018,150(4):1065-1081
Phenotypic traits are regularly used to diagnose the development of Fusarium head blight (FHB) in the field, whereas mycotoxin accumulation in wheat grains can only be accurately evaluated through costly methods, such as high–performance liquid chromatography (HPLC). The aim of this study was to determine whether: (i) the results provided by existing commercial decision support tools could be anticipated using phenotypic measurements, including a novel technique of computer–assisted image analysis of spikes; and (ii) these measurements could avoid using HPLC. We monitored the FHB development during two consecutive years in highly contaminated plots in the Burgundy region (France). Contamination by crop residues was simulated through a field inoculation with barley grains artificially colonized by Fusarium graminearum. The development of the disease on spikes and harvested grains was assessed on one tolerant and two susceptible wheat varieties. The accumulated amounts of mycotoxins were measured in harvested grains using HPLC. As expected, the measured traits revealed that the inoculum responsible for infection on spikes mainly came from residues left on the soil surface, and the susceptible varieties were more diseased than the tolerant variety. Weather conditions had a strong effect on disease development. The novel computer–assisted image analysis technique had a better prediction power of deoxynivalenol accumulation, was more objective and time–saving than classical visual symptom assessments. This assessment method could be suitable to supplement the use of existing prediction tools and might avoid systematic and costly mycotoxin measurements in likely infected plots. 相似文献
130.
Juan Carlos Vences-Benitez Verónica Martínez-Miranda Ivonne Linares-Hernández Perla Tatiana Almazán-Sánchez Guadalupe Vázquez-Mejía 《Water, air, and soil pollution》2017,228(10):393
The goal of this research was the electrooxidation (EO) of a nonionic surfactant nonylphenol decaethoxylate (NP-10) in aqueous solution and denim wastewater. Three different configuration systems were evaluated in batch cells using a boron-doped diamond (BDD) anode; copper, iron, and BDD were used as cathodes. The EO process was carried out in a batch process, in a glass cell with a capacity of 1000 mL. The anode surface area was 0.0307 m2 and 1–3 A of current intensity were applied (3, 6, 10 mA/cm2) with an electrolysis time of 240 min for aqueous solution and 780 min for denim wastewater in order to investigate the degradation of the surfactant. The processes were analyzed in terms of chemical oxygen demand (COD) and total organic carbon (TOC). The maximum mineralization efficiency in aqueous solution for the BDD-Cu electrooxidation system was 92.2% for COD and 45.6% for TOC at pH 2 and 3 mA/cm2 of current intensity. For denim wastewater, the removal efficiency was 44.1% for COD and 26.5% for TOC at pH 4.5 and 6 mA/cm2 of current intensity, using a BDD-BDD system. The raw and treated (aqueous solution and denim) wastewater were characterized by UV-Vis and infrared spectroscopy. 相似文献