Stress sensitivity of formation during multi-cycle gas injection and production in an underground gas storage rebuilt from gas reservoirs

Permeability sensitivity to stress experiments were conducted on standard core samples taken from Wen 23 Gas Storage at multi-cycle injection and production conditions of the gas storage to study the change pattern of stress sensitivity of permeability.A method for calculating permeability under overburden pressure in the multi-cycle injection and production process was proposed,and the effect of stress sensitivity of reservoir permeability on gas well injectivity and productivity in UGS was analyzed.Retention rate of permeability decreased sharply first and then slowly with the increase of the UGS cycles.The stress sensitivity index of permeability decreased with the increase of cycle number of net stress variations in the increase process of net stress.The stress sensitivity index of permeability hardly changed with the increase of cycle number of net stress variations in the decrease process of net stress.With the increase of cycle number of net stress variation,the stress sensitivity index of permeability in the increase process of net stress approached that in the decrease process of net stress.The lower the reservoir permeability,the greater the irreversible permeability loss rate,the stronger the cyclic stress sensitivity,and the higher the stress sensitivity index of the reservoir,the stronger the reservoir stress sensitivity.The gas zones with permeability lower than 0.3’10-3 mm2 are not suitable as gas storage regions.Stress sensitivity of reservoir permeability has strong impact on gas well injectivity and productivity and mainly in the first few cycles.

Linkages between soil microbial stability and carbon storage in the active layer under permafrost degradation

The Qinghai-Tibet Plateau(QTP)distributes the largest extent of high-altitude mountain permafrost in the world(Zou et al.,2017),which has different characteristics from high-latitude permafrost(Yang et al.,2010)and stores massive soil carbon.

NDMP-Plus： An Improved Protocol for Network Based Data Management

Network based data management is the backup/restore mechanism used in a data storage center. This paper presents a new network based data management-NDMP-Plus, a revision of network data management protocol. Components and the working mechanism of the NDMP-Plus architecture are first discussed. Two new techniques in NDMP-Plus-virtual storage layer （VSL） and negotiation mechanism are then studied. VSL is a crucial component to achieve flexibility, and the negotiation mechanism is a key to improve performance. Furthermore, experiments are carried out to evaluate the performance of NDMP-Plus. The result suggests that NDMP-Plus has stronger flexibility and better performance than NDMP.

Fast-response,high-stability,and high-efficiency full-color quantum dot light-emitting diodes with charge storage layer

Recently,solution-processed quantum dot lightemitting diodes(QLEDs)have emerged as a promising candidate for next-generation lighting and display devices.However,when given a constant voltage or current,the QLEDs need a certain working time to reach their maximum brightness.Such positive aging challenge,dramatically reducing the response speed of the device and causing a luminescence delay,is urgent to be investigated and resolved.In the current work,we introduce a charge-storage layer architecture by inserting copper(I)thiocyanate(CuSCN)between the organic holeinjection layer and hole-transport layer.The extracted holes will be released during the next electrical signal stimulation to increase the efficiency of charge transport.As a result,the response speed of the QLEDs is improved by an order of magnitude.In addition,by inserting an inorganic CuSCN layer,the efficiency,lifetime,and environmental stability of red/green/blue full-color QLEDs are enhanced simultaneously.Moreover,this work provides a generic strategy for the fabrication of fast-response and high-efficiency full-color QLEDs without luminescence delay,which plays a critical role in the practical industrialization of QLEDs.