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711.
712.
以2种不同纳米级锐钛型TiO2为载体负载V2O5和WO3制备得到脱氮催化剂H和Z,在自制固定床反应器中测试其DeNOx活性,结果表明,催化剂H的活性比催化剂Z低得多.利用XRD、BET、FT-IR和SEM等手段对2种催化剂进行比较,BET表面积虽然会对DeNOx活性产生一定的影响,但催化剂H主要因为活性物质V2O5和载体TiO2发生反应,生成V3Ti6O17,导致其DeNOx活性大幅下降,而在催化剂Z中TiO2仍然保持锐钛型,未与V2O5发生反应. 相似文献
713.
研究了负载型TiO2光催化剂在印染废水降解中的失活及其产生的原因。实验结果说明,催化剂活性下降的主要原因有:废水中不溶于水的染料等悬浮物和催化反应中产生的无定形碳在催化剂表面的吸附;高含量的无机离子对催化剂活性位的占据或在表面的沉积;长时间的使用和反复冲洗使TiO2负载量减少。通过同时采用灼烧和酸洗的方法可以使TiO2的活性恢复到新催化剂的69.5%。 相似文献
714.
S.?AlbonettiEmail author S.?Blasioli M.?Bugani C.?Lehaut-Burnouf S.?Augustine E.?Roncari F.?Trifirò 《Environmental Chemistry Letters》2003,1(3):197-200
The aim of the plesent investigation was to study the effect of SiO2 addition on the thermal deactivation of V2O5/WO3/TiO2 catalysts used for NOx pollution abatement. The results suggest that the degradation of the catalytic properties is strongly correlated to the structural ageing which is, in turn, mainly related to the anatase–rutile phase transformation and to the WO3 phase segregation. The addition of SiO2 strongly influences the temperature at which these phenomena occur. In fact, it was found that the introduction of this oxide stabilizes the material, retarding the collapse of surface area, and increases the temperature of the anatase to rutile phase transition. 相似文献
715.
T. N. Angelidis E. Tourasanidis E. Marinou G. A. Stalidis 《Resources, Conservation and Recycling》1995,13(3-4)
The petroleum refining industry makes extensive use of catalysts, containing critical metals, such as, Mo, Co and Ni, for the desulphurization of various oil fractions. The selective recovery of these metals from two uncrushed and at low temperature calcined industrial hydrodesulphurization (Mo---Co/Al2O3 and Mo---Ni/Al2O3---SiO2) catalysts was studied, applying a two-step alkali-acid procedure. Fundamental kinetic aspects of the process, such as, reaction time, leaching reagents concentration and reaction temperature, were studied. Recoveries up to 97% for Mo and up to 92% for Co or Ni in separate solutions were achieved, using low cost and easily available reagents, such as sodium hydroxide and sulphuric acid. 相似文献
716.
717.
介绍了大庆石化总厂醋酸装置投用后废水处理、废渣循环利用及废水综合治理的情况,并对今后治理污染提出了初步设想。 相似文献
718.
719.
Jeong-Geol Na Byung-Hwan Jeong Soo Hyun Chung Seong-Soo Kim 《Journal of Material Cycles and Waste Management》2006,8(2):126-132
Catalytic pyrolysis of low-density polyethylene (LDPE) was investigated using various fly ash-derived silica–alumina catalysts
(FSAs). FSAs were prepared by a simple activation method that basically includes NaOH treatment of fly ash by a fusion method,
followed by an aging process. A series of LDPE pyrolysis experiments was conducted and the catalytic performance of FSAs was
assessed in terms of the degradation temperature and the simulated boiling point distribution of the liquid products. The
effects of synthesis conditions such as NaOH/fly ash weight ratio and aging time were examined by X-ray diffractometer (XRD),
Brunauer-Emmett-Teller (BET) surface area analyzer, and scanning electron microscope to clarify the controlling factors affecting
the catalytic activity. To obtain catalyst with high activity, it is necessary to produce sufficient silica and alumina species
that can be easily co-precipitated into solid acid catalyst by destruction of the fly ash structure and to optimize the activation
time for catalyst synthesis to prevent the transformation into inactive phases. The catalytic performance of FSA obtained
from optimal conditions was equivalent to that of commercial catalysts, demonstrating the effectiveness of the catalyst. 相似文献
720.
Gunung Oh Seo Yoon Park Myung Won Seo Ho Won Ra Tae Young Mun Jae-Goo Lee 《International Journal of Green Energy》2019,16(4):333-349
Cracking, steam reforming, dry reforming, and combined steam and dry reforming of toluene in model syngas were performed using catalysts to simulate tar removal produced during biomass gasification. The catalysts were prepared by adding Ru, Ca, and Mn to Ni-based catalysts, and their properties were measured using BET, pulse CO chemisorption, XRD and TG. In steam and dry reforming of toluene, a high toluene conversion was observed with increasing Ca content in the catalyst and catalysts containing Ca showed a higher activity than those containing Mn. In combined steam-dry reforming with syngas, 1%CaNiRu/Al2O3 indicated a conversion of 93.9% at 800°C. 相似文献