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Xiao J.,CAS Dalian Institute of Chemical Physics | Pan X.,CAS Dalian Institute of Chemical Physics | Guo S.,CAS Dalian Institute of Chemical Physics | Guo S.,Shaanxi Yanchang Petroleum Group Co. | And 2 more authors.
Journal of the American Chemical Society | Year: 2015

An increasing number of experimental studies have demonstrated that metal or metal oxide nanoparticles confined inside carbon nanotubes (CNTs) exhibit different catalytic activities with respect to the same metals deposited on the CNT exterior walls, with some reactions enhanced and others hindered. In this article, we describe the concept of confinement energy, which enables prediction of confinement effects on catalytic activities in different reactions. Combining density functional theory calculations and experiments by taking typical transition metals such as Fe, FeCo, RhMn, and Ru as models, we observed stronger strains and deformations within the CNT channels due to different electronic structures and spatial confinement. This leads to downshifted d-band states, and consequently the adsorption of molecules such as CO, N2, and O2 is weakened. Thus, the confined space of CNTs provides essentially a unique microenvironment due to the electronic effects, which shifts the volcano curve of the catalytic activities toward the metals with higher binding energies. The extent of the shift depends on the specific metals and the CNT diameters. This concept generalizes the diverse effects observed in experiments for different reactions, and it is anticipated to be applicable to an even broader range of reactions other than redox of metal species, CO hydrogenation, ammonia synthesis and decomposition discussed here. © 2014 American Chemical Society.


Li J.,Shaanxi Yanchang Petroleum Group Co.
Xiandai Huagong/Modern Chemical Industry | Year: 2016

There is a serious abnormal phenomena (weak reaction) in 200 kt/a polypropylene unit of Yan'an petrochemical plant. The influencing factors, including catalyst, hydrogen source, propylene tail gas recovery system, deactivation system, propylene feedstock, and so on, are analyzed. It is confirmed that relatively higher content of water and CO in propylene feedstock is attributed to the weak reaction phenomena. By strengthening the regeneration of molecular sieve and adjusting the operation of dethanizing column and stripping column, the contents of water and CO in propylene feedstock all can reach the requirements of index. The polymerization reaction is gradually improved and the device is returned to normal conditions. © 2016, China National Chemical Information Center. All right reserved.


Wang X.,Shaanxi Yanchang Petroleum Group Co.
Energy Exploration and Exploitation | Year: 2015

Southern Ordos Basin contains plentiful oil and gas shale resources in the Mesozoic and Upper Paleozoic. It is known that the surface in this region is covered by thick loess layers with severe variations in tomography, thickness and velocity. The adverse surface conditions result in complex statics problems and heavy scattering noise and also cause serious absorption of high-frequency energy. Conventional seismic surveys obtain poor quality seismic data, which could hardly be used to obtain information about gas shale reservoirs. In order to study strong heterogeneous gas shale reservoirs and improve the success rate of horizontal wells, a new 3D seismic survey was acquired in the typical loess plateau area by using the WesternGeco UniQ integrated point-receiver land seismic system. The new survey is designed as full-azimuth, high-density, point-source/point-receiver in order to fully sample the seismic wavefield and avoid the irreversible signal damage caused by conventional field array techniques. By taking advantage of the benefits of UniQ seismic data, targeted data processing sequence is given to resolve the specific complicated statics and noise attenuation problems. Compared with the previously acquired 2D crooked line high-resolution seismic data in the gullies, the result of UniQ seismic data exhibits significant improvement both in the single-to-noise ratio (SNR) and the image quality of target layers. This indicates that the UniQ seismic data will be more feasible to facilitate gas shale characterization.


Wang X.,Shaanxi Yanchang Petroleum Group Co.
Shiyou Xuebao/Acta Petrolei Sinica | Year: 2016

With the enhanced geological knowledge, Yanchang Petroleum Group has clarified that the north Shaanxi slope of Ordos Basin has favorable geological conditions for the formation of unconventional natural gas; tight sandstone gas and shale gas are the most practical exploration and development fields. In terms of geological exploration concept, it has been determined that the provenance of the southern Ordos Basin made a great contribution to the development of Paleozoic sand bodies; frequent transgression and regression is the most favorable factor for promoting the development of high-quality reservoirs. The accumulation mode of "mature hydrocarbon kitchen migration for reservoir control" was created to predict the spatial distribution of tight sandstone gas reservoirs. This study focuses on the gas occurrence capacity of sandy laminae developed in terrestrial shale, aiming to find the occurrence space of free gas. The assemblage of multi-disciplines including geochemistry, reservoir, logging and seismology was used for seismic prediction in the sweet-spot of shale gas reservoirs. Meanwhile, the large-scale exploitation of tight sandstone gas and shale gas is guaranteed by applying horizontal-well drilling and completion technologies for terrestrial shale gas, drilling fluid system with reservoir protection function for tight sandstone gas reservoirs, VES-CO2 foam fracturing technology, liquid CO2/slick water mixing fracturing technology and other development technologies. Guided by the integrated exploration and development mode, the geological reserves of Mesozoic shale gas reserves and Paleozoic tight sandstone gas were proven to be 677×108m3 and 3 000×108m3 respectively, and current natural gas production capacity has reached 6× 108m3/a, basically changing the situation of oil development in the south while natural gas production in the north. © 2016, Science Press. All right reserved.


Trademark
Shaanxi Yanchang Petroleum Group Co. | Date: 2014-01-20

Aeroplanes; Automobiles; Bicycles; Boats; Cable cars; Land vehicles; Pneumatic tyres and inner tubes for motorcycles; Tires; Tires for vehicle wheels; Tyres, solid, for vehicle wheels.


Trademark
Shaanxi Yanchang Petroleum Group Co. | Date: 2014-12-08

Aeroplanes; Anti-skid studs for vehicle tires; Bicycles; Boats; Cable cars; Cars; Spare tire covers; Tires for vehicle wheels; Treads for retreading tyres; Tyres, solid, for vehicle wheels.


Trademark
Shaanxi Yanchang Petroleum Group Co. | Date: 2014-12-08

Aeroplanes; Anti-skid studs for vehicle tires; Bicycles; Boats; Cable cars; Cars; Spare tire covers; Tires for vehicle wheels; Treads for retreading tyres; Tyres, solid, for vehicle wheels.


Trademark
Shaanxi Yanchang Petroleum Group Co. | Date: 2014-12-08

Aeroplanes; Anti-skid studs for vehicle tires; Bicycles; Boats; Cable cars; Cars; Spare tire covers; Tires for vehicle wheels; Treads for retreading tyres; Tyres, solid, for vehicle wheels.


Trademark
Shaanxi Yanchang Petroleum Group Co. | Date: 2014-12-08

Aeroplanes; Anti-skid studs for vehicle tires; Bicycles; Boats; Cable cars; Cars; Spare tire covers; Tires for vehicle wheels; Treads for retreading tyres; Tyres, solid, for vehicle wheels.


Trademark
Shaanxi Yanchang Petroleum Group Co. | Date: 2014-12-08

Aeroplanes; Anti-skid studs for vehicle tires; Bicycles; Boats; Cable cars; Cars; Spare tire covers; Tires for vehicle wheels; Treads for retreading tyres; Tyres, solid, for vehicle wheels.

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