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71.
Effect of carbon tetrachloride on sonochemical decomposition of methyl orange in water 总被引:2,自引:0,他引:2
Two types of sonicators were used for the sonochemical decomposition of methyl orange (MO) in the presence and absence of carbon tetrachloride (CCl4): One is a 45kHz ultrasonic cleaning bath (a low intensity sonicator) and the other is a 200kHz ultrasonic reactor (a high intensity sonicator). It was clearly confirmed that the rates of the sonochemical decomposition of MO increased with increasing the concentration of CCl4 in both sonicators. The enhancement effect of CCl4 was much higher in the high intensity sonicator than in the low intensity one: by the addition of 100ppm of CCl4, the decomposition ratio of MO with the high intensity sonicator became 41 times larger, while that with the low intensity sonicator became 4.8 times larger. Based on the obtained results, it was suggested that the formed cavitation phenomenon was different between sonicators. It was also suggested that the sonochemical decomposition of MO in the presence of CCl4 would be useful to evaluate the sonochemical efficiency, because the rate of MO decomposition can be effectively enhanced by the sonolysis of CCl4. 相似文献
72.
Hersília de Andrade e Santos Paulo dos Santos Pompeu Danilo Okuma Lessa Kenji 《Regional Environmental Change》2012,12(1):123-132
Flow regulation causes various environmental impacts in the downstream reaches of impounded rivers. The S?o Francisco River
(SF) basin is Brazil’s third most important watershed. Several dams have been built in its course in the last four decades,
mostly for flow regulation and hydropower generation. This paper presents an evaluation of historical changes in the flood
regime. Three regions of the SF River basin, which are under the influence of different levels of regulation, were studied:
the lower, middle, and upper SF River. The components of magnitude, frequency, and duration of floods were quantified for
each region from 1940 to 1960 (prior to the construction of the first dam) and from 1986 to 2006 (after the last dam). The
results have shown the inexistence of big floods in the downstream areas, decreasing durations of small floods as well as
significant changes in the annual seasonality of floods. Reductions in the flood frequency were verified in all stretches,
even in non-regulated systems, such as the lower Velhas River. The climate variation, which occurred in both period, was not
able to explain the changes in the flood regime of S?o Francisco River; therefore, dams and other anthropogenic activity are
the main factors promoting the temporal variability of streamflows in the S?o Francisco basin. 相似文献
73.
74.
75.
Kenji?YoshinoEmail author Tsunenori?Koga Sayaka?Oki 《Behavioral ecology and sociobiology》2011,65(9):1825-1832
To understand the evolution of weapons, we must understand both their functions and relative importance compared to body size
in determining fighting success. Many decapod crustaceans develop disproportionately large chelipeds for their body size and
use them as a weapon in agonistic interaction. There are, however, examples where weapons are merely signals of resource holding
potential (RHP) and the RHP is actually determined by body size. We investigated the function and relative efficacy of body
size and major cheliped size in male–male contests for females in the hermit crab Diogenes nitidimanus. Contests over females took two forms: (1) males preemptively guarded females and opponents did not fight with the guarding
male. Cheliped size contributed significantly to the settlement of these contests and probably functioned as a visual signal
for the opponents. (2) Guarding males engaged in physical combat with an opponent. In these cases, both body and cheliped
sizes affected contest outcomes. The effect size for cheliped size was as strong, or stronger, than that for body size. These
results suggest that large chelipeds have evolved as a true weapon and are effective in escalated fights for resources. Therefore
they are also efficient visual signals for settling contests with only display. Our results are a rare example that clearly
demonstrate that weapons are a more important determinant of fights than body size when both body and weapon size affect resource
acquisition. 相似文献
76.
Tsutomu Kobayashi Yueqin Tang Toyoshi Urakami Shigeru Morimur Kenji Kida 《环境科学学报(英文版)》2014,26(2):423-431
Sweet potato shochu is a traditional Japanese spirit produced mainly in the South Kyushu area in Japan. The amount of stillage reaches approximately 8 × 105tons per year. Wastewater mainly containing stillage from the production of sweet potato-shochu was treated thermophilically in a fullscale treatment plant using fixed-bed reactors(8 reactors × 283 m3). Following the addition of Ni2+ and Co2+, the reactors have been stably operated for six years at a high chemical oxygen demand(COD) loading rate of 14 kg/(m3·day). Analysis of coenzyme content and microbial communities indicated that similar microbial communities were present in the liquid phase and on the fiber carriers installed in reactors. Bacteria in the phyla Firmicutes as well as Bacteroidetes were dominant bacteria, and Methanosarcina thermophila as well as Methanothermobacter crinale were dominant methanogens in the reactors. This study reveals that stillage from sweet potato-shochu production can be treated effectively in a full-scale fixed-bed reactor under thermophilic conditions with the help of Ni2+and Co2+. The high diversity of bacterial community and the coexistence of both aceticlastic and hydrogenotrophic methanogens contributed to the excellent fermentation performance. 相似文献
77.
78.
When light (> 370 nm) was allowed to interact with an aqueous solution containing dissolved organic matter (DOM) and Fe(III), removal of aniline (AN) was observed. This was due to the photocatalytic reaction of Fe(III) mediated by DOM. Syringic acid (SYA) and humic acid (HA) were used as DOM in the present study. The 15N‐NMR spectrum of the product mixture from the light irradiation of the SYA/Fe(III) system demonstrated that AN was covalently bound to SYA. The kinetics of AN removal were, therefore, interpreted by assuming covalent binding between DOM and AN. The amounts of covalent binding sites and the apparent second‐order rate constants could be evaluated, and the amounts of covalent binding sites decreased with the increases of the concentration of DOM. This is attributed that the polymerization of DOM by the photo‐oxidation competed with the covalent binding between AN and DOM. 相似文献
79.
E.D.?David?MorganEmail author John?M.?Brand Kenji?Mori Sarah?J.?Keegans 《Chemoecology》2004,14(2):119-120
Summary. The major component of the trail pheromone of
the myrmicine ant Crematogaster castanea
has been identified as (R)-2-dodecanol from
the tibial glands of the hind legs. The substance gave activity comparable to the
contents of 8 tibial glands at a concentration of 1 pg per 32 cm trail. 相似文献
80.
Osamu Abe Wenshou Wei Masao Mikami Kenji Kosugi Junrong Xu Takeshi Sato Mingzhe Liu Masujiro Shimizu Atsushi Sato 《Water, Air, & Soil Pollution: Focus》2005,5(3-6):3-13
Four automatic weather stations (AWS) were installed on the slopes and foot areas of the Tianshan and Kunlun Mountains along
a longitude of 80 degrees east: (1) Taglak 2400 m a.s.l., (2) Aksu 1000 m, (3) Kartash 2800 m, and (4) Qira 1700 m. These
two slopes face the Taklimakan Desert. Tagliak lies on the southern slope of Tianshan, and Kartash on the northern slope of
Kunlun. The meteorological characteristics of the mountainous regions were investigated using surface data obtained during
an intensive observation period (IOP) in spring 2002. It was found that visibility on the slopes decreases in the daytime,
and there is no relationship between visibility and wind speed in the mountainous areas. Two snow layers containing dust particles
were observed in the snow cover in Taglak during the IOP in spring 2003. These results suggest that a warm air parcel containing
aeolian dust climbs over the slopes of the mountainous areas, and dust particles in the mountainous areas are transported
from the foot areas. 相似文献