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631.
DO和pH值在短程硝化中的作用 总被引:16,自引:0,他引:16
在SBR反应器中对DO和pH值在短程硝化和半亚硝化过程中的作用进行试验研究,结果表明,控制低DO和适宜的pH值在短程硝化过程中起着重要的作用。本试验条件下。当DO为0.5~1.0mg/L、pH值为7.5—8.0时。在SBR反应器中很容易实现短程硝化;当DO〉0.3mg/L时,DO越低,出水NO2^-N积累率越高;当pH值〉6.8时,不会影响系统NO2^-N积累的稳定性。另外,研究结果还表明,通过控制DO和pH值可以实现半亚硝化。本试验条件下,当进水氨氮浓度为120mg/L时,控制DO为0.3—0.4mg/L可实现出水半亚硝化;当进水氨氮浓度为200mg/L时,控制DO为0.5—0.6mg/L或pH值为6.8也可以实现出水半亚硝化。 相似文献
632.
油田稠油污水生物处理技术研究 总被引:5,自引:3,他引:5
针对稠油污水的特点,利用序批式生物反应器SBR对微生物进行了培养、驯化进而在稠油污水中生存、繁殖试验,并对其中的有机物进行了降解转化,生成稳定的CO2、H2O、NH3,利用该方法可以对稠油污水进行净化处理。试验结果表明,采用SBR工艺可使原水中CODCr从323 mg/L降至72 mg/L,去除率为77.7%;BOD从90 mg/L降至14.4 mg/L,去除率为84%;悬浮物从200 mg/L降至47 mg/L,去除率为76.5%。成功地解决了稠油污水的达标外排问题。 相似文献
633.
农药厂家的综合废水通过选择合理的工艺路线 ,提高废水的可生化性 ,经过二级生化处理后的出水经絮凝沉降后达标排放。 相似文献
634.
Zeng Wei Peng Yongzhen Wang Shuying 《Frontiers of Environmental Science & Engineering in China》2007,1(1):28-32
In order to improve the nitrogen removal efficiency and save operational cost, the feasibility of the alternating aerobic-anoxic
process (AAA process) applied in a sequencing batch reactor (SBR) system for nitrogen removal was investigated. Under sufficient
influent alkalinity, the AAA process did not have an advantage over one aerobicanoxic (OAA) cycle on treatment efficiency
because microorganisms had an adaptive stage at the alternating aerobic-anoxic transition, which would prolong the total cycling
time. On the contrary, the AAA process made the system control more complicated. Under deficient influent alkalinity, when
compared to OAA, the AAA process improved treatment efficiency and effluent quality with NH4
+-N in the effluent below the detection limit. In the nitrification, the average stoichiometric ratio between alkalinity consumption
and ammonia oxidation is calculated to be 7.07 mg CaCO3/mg NH4
+-N. In the denitrification, the average stoichiometric ratio between alkalinity production and NO3
−-N reduction is about 3.57 mg CaCO3/mg NO3
−-N. As a result, half of the alkalinity previously consumed during the aerobic nitrification was recovered during the subsequent
anoxic denitrification period. That was why the higher treatment efficiency in the AAA process was achieved without the supplement
of bicarbonate alkalinity. If the lack of alkalinity in the influent was less than 1/3 of that needed, there is no need for
external alkalinity addition and treatment efficiency was the same as that under sufficient influent alkalinity. Even if the
lack of alkalinity in the influent was more than 1/3 of that needed, the AAA process was an optimal strategy because it reduced
the external alkalinity addition and saved on operational cost.
Translated from Acta Scientiae Circumstantiae, 2004, 24(4): 576–580 [译自: 环境科学学报] 相似文献
635.
636.
Dr. J. A. M. A. Tan J. S. H. Tay L. I. Lin S. K. Y. Kham J. N. Chia T. M. Chin Norkamar Bt. Adb. Aziz H. B. Wong 《黑龙江环境通报》1994,14(11):1077-1082
β-Thalassaemia major patients have chronic anaemia and since 3–4 per cent of Singaporeans carry the β-gene, prenatal diagnosis is essential. We evaluated the amplification refractory mutation system (ARMS) technique as a routine test for prenatal diagnosis of β-major. Six mutations along the β-gene were studied—41–42 (-TCTT), IVSII #654 (C-T), 17β (A-T), – 28 TATA (A-G), IVSI #5 (G-C), and IVSI #1 (G-T). Our results indicate that prenatal diagnosis using these mutations can be offered to 90 per cent (35/39) of our Chinese couples and 54·6 per cent (12/22) of our Malay couples at risk. Confirmation of ARMS results was carried out using allele-specific oligonucleotide hybridization. Prenatal diagnosis using ARMS was successfully carried out in nine cases which included a set of triplets and twins. The triplets were diagnosed with the β-trait carrying the 41–42 mutation. The couple with twins possessed the #654 mutation and one twin was diagnosed with the β-trait and the other with #654 homozygosity. Genomic sequencing of the undefined mutations in the Chinese couples revealed rarer mutations at − 29 and an ATG-AGG base substitution at the initiation codon for translation. In the Malay couples, genomic sequencing detected mutations at codon 15 (TGG-TAG) and codon 26 (GAG-AAG). We conclude that ARMS with its direct detection of amplified products by gel electrophoresis provides an accurate, rapid, and simpler method for our β-thalassaemia prenatal diagnosis programme in Singapore. 相似文献
637.
ASBR处理热水解污泥的启动试验研究 总被引:6,自引:1,他引:6
进行了中温、高温厌氧序批式反应器(ASBR)处理热水解污泥的启动试验,同时与中温连续流搅拌反应器(CSTR)进行对比,ASBR 启动期包括种泥驯化期、过渡期和稳态期 3 个阶段.启动过程中污泥固体物质在 ASBR 中不断积累而保持较高的固体停留时间(SRT),有助于提高处理效率.污泥中蛋白质生化降解产生的氨氮提高了体系的缓冲能力,pH值保持在 6.60~7.72之间.当水力停留时间(HRT)为 20d、容积负荷为 2.71kg COD/(m3d) 时,中温 ASBR、高温 ASBR 和中温 CSTR 的总 COD(TCOD)去除率分别为 67.71%、64.55%、60.25%.相应地, ·中温、高温 ASBR 的平均日产气量比中温 CSTR 分别提高 15%、10%. 相似文献
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