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111.
为准确表征煤层气藏强化开采过程中的复杂地质力学效应,同时考虑多孔介质全组份多过程物质运移特征,构建了煤层气藏强化开采全流固耦合数学模型,开发了相应的数值模拟算法,并据此进一步剖析了地质力学效应以及注入气组成对孔渗参数及注采指标的影响。结果表明,有效应力效应与基质膨胀/收缩作用均可显著地影响孔隙度与渗透率,但两者作用方向相反,注入CO2诱发的基质膨胀可使注入井附近渗透率损失近90%。随着杨氏模量的增大或者基质形变强度的降低,CO2突破时间提前,导致煤层气产量及CO2埋存量降低。研究成果可为煤层气产能准确预测及高效开发提供技术支持。 相似文献
112.
《The Electricity Journal》2021,34(7):107002
Environmental justice (EJ) and climate justice are becoming central foci of climate policy. Awareness is also growing on the need for some amount of carbon dioxide removal (CDR) to curb warming to 1.5 °C. In this paper we map dimensions of environmental and climate justice that stakeholders and communities will need to consider -- from local to global scales. Mapping issues is a step towards developing frameworks to undertake CDR in an environmentally just way. 相似文献
113.
Cheol Park Won Sup Lee Se-Il Go Sang-Ho Jeong Jiyun Yoo Hee-Jae Cha Young-Joon Lee Heui-Soo Kim Sun-Hee Leem Hye Jung Kim Gon Sup Kim Soon-Chan Hong Yung Hyun Choi 《International journal of molecular sciences》2021,22(6)
Evidence suggests that augmented expression of a certain gene can influence the efficacy of targeted and conventional chemotherapies. Here, we tested whether the high expression of enhancer of the rudimentary homolog (ERH), which serves as a prognostic factor in some cancers, can influence the efficacy of anthocyanins isolated from fruits of Vitis coignetiae Pulliat, Meoru in Korea (AIMs) on human gastric cancer cells. The anticancer efficacy of AIMs was augmented in ERH-transfected MKN28 cells (E-MKN28 cells). Molecularly, ERH augmented AIM-induced caspase-dependent apoptosis by activating caspase-3 and -9. The ERH-augmented apoptotic effect was related to mitochondrial depolarization and inhibition of antiapoptotic proteins, XIAP, and Bcl-2. In addition, reactive oxygen species (ROS) generation was augmented in AIMs-treated E-MKN28 cells compared to AIMs-treated naïve MKN28 cells. In conclusion, ERH augmented AIM-induced caspase-dependent mitochondrial-related apoptosis in MKN28 cells. A decrease in expression of Bcl-2 and subsequent excessive ROS generation would be the mechanism for ERH-augmented mitochondrial-related apoptosis in AIMs-treated MKN28 cells. A decrease in expression of XIAP would be another mechanism for ERH-augmented caspase-dependent apoptosis in AIMs-treated MKN28 cells. 相似文献
114.
Shishan Xue Guanfei Liu Jingjuan Lai Peng An Yang Liu Yuanpeng Wu Yu Wang Zhiyong Ye Qiao Tang Hongwei Zhou 《大分子材料与工程》2021,306(11):2100415
Self-healing hydrogels often possess poor mechanical properties which largely limits their applications in many fields. In this work, boron nitride nanosheets are introduced into a network of the poly(vinyl alcohol)/borax (PVA/borax) hydrogels to enhance the mechanical properties of the hydrogel without compromising the self-healing abilities. The obtained hydrogels exhibit excellent mechanical properties with a tensile strength of 0.410 ± 0.007 MPa, an elongation at break of 1712%, a Young's Modulus of 0.860 ± 0.023 MPa, and a toughness of 3.860 ± 0.075 MJ m−3. In addition, the self-healing efficiency of the hydrogels is higher than 90% within 10 min at room temperature. Benefiting from the excellent self-healing properties, the shapeability of the hydrogel fragments is observed using different molds. In addition, the hydrogels display rapid pH-driven shape memory effects and can recover to their original shape within 260 s. Overall, this work provides a new approach to hydrogels with integrated excellent mechanical properties, self-healing abilities, and rapid pH-driven shape memory effects. 相似文献
115.
116.
采用相互兼顾的原则,进行中小批量的铸铁车间就地技术改造,较好地解决了工人劳动强度、作业环境、铸件质量、产量与技改投入的矛盾。 相似文献
117.
四异丁氧基镍酞菁的合成及其溶剂效应 总被引:2,自引:0,他引:2
4 异丁氧基邻苯二腈与氯化镍在强有机碱 1 ,8 二氮杂双环 (5 ,4,0 )十一碳烯 7催化下反应 ,合成了四异丁氧基镍酞菁 ,产物经FT -IR、元素分析、UV -Vis吸收光谱和1 H NMR表征了结构 ;并研究了其溶剂效应 ,结果表明 :最大吸收峰波数ν与函数 f(n ,ε)存在一定的线性关系 ,线性相关系数为 0 940 2 ,而Bayliss函数项 (n2 - 1 ) /(2n2 +1 )决定了最大吸收波长 (λmax)的位移变化 ;化合物的λmax在不同溶剂中随聚集程度增加 ,发生一定程度的蓝移 相似文献
118.
Methane Transport Capacity of Rice Plants. II. Variations Among Different Rice Cultivars and Relationship with Morphological Characteristics 总被引:3,自引:0,他引:3
M.S. Aulakh J. Bodenbender R. Wassmann H. Rennenberg 《Nutrient Cycling in Agroecosystems》2000,58(1-3):367-375
Of the total methane (CH4) emitted from a rice field during the growing season 60–90% is emitted through the rice plants. We determined the methane transport capacity (MTC) of rice plants at different physiological growth stages using an automatic measuring system under greenhouse conditions. A total of 12 cultivars (10 inbred varieties and 2 hybrids) were studied in sets of two experiments and was distinguished into three groups according to the patterns of MTC development. MTC is generally increasing from seedling stage to panicle initiation (PI), but differs in the development from PI to maturity. While the hybrid showed a gradual increase in MTC, the inbred cultivars showed either minor changes in MTC or a drastic decrease from flowering to maturity. Among tall cultivars, Dular showed the highest MTC, followed by B40; the lowest MTC was found in Intan. High-yielding dwarf cultivars showed MTC in the descending order of IR72 > IR52 > IR64 > PSBRc 20. New plant type cultivars showed very low MTC with IR65600 exhibiting the smallest MTC at PI, flowering, and maturity. Hybrids (Magat and APHR 2) showed the largest MTC that continued to increased with plant growth. The MTC patterns were attributed to growth parameters and the development of morphological characteristics of the aerenchyma. These results suggest that in tall, dwarf, and NPT cultivars, increase in root or aboveground biomass during initial growth determines a corresponding increase in MTC. Once aerenchyma has fully developed, further increase in plant biomass would not influence MTC. However, in the case of hybrids, a positive relationship of MTC with root + shoot biomass (r = 0.672, p 0.05) and a total plant biomass including grain (r = 0.849, p 0.01) indicate continuous development of aerenchyma with plant growth, resulting in enhanced MTC. In all cultivars, tiller number, but not height, was linearly related to MTC, indicating that the number of outlets/channels rather than plant size/biomass determines the transport of CH4. These results clearly demonstrate that rice cultivars differ significantly in MTC. Therefore, the use of high-yielding cultivars with low MTC (for example, PSBRc 20, IR65598, and IR65600) could be an economically feasible, environmentally sound, and promising approach to mitigate CH4 emissions from rice fields. 相似文献
119.
In this paper, a cooperative control analysis and design method is investigated for heterogeneous dynamical systems that may be of arbitrary relative degree or nonminimum-phase or both. To achieve consensus or cooperative stability, a negative value of input-feedforward passivity index is used to accommodate and analyze such systems, and the magnitude of the index value is also used as the impact coefficient to quantify the impacts of heterogeneous dynamics of these systems on their networked operations. Physical-system-level designs are explicitly carried out to make individual linear and nonlinear systems (which are either feedback linearizable or nonminimum phase of certain form) become passivity-short and to embed one pure integrator into their input–output dynamics. The network-level distributed control can simply be chosen without any knowledge of the heterogeneous dynamics but with only information of an upper bound on their impact coefficients. It is shown, using the impact equivalence principle, that these controls separately designed but implemented together always ensure either local or global consensus and that a global non-trivial consensus emerges if and only if the information network has at least one globally reachable node or is varying but cumulatively connected. The proposed methodology of fully modularized designs unravels complexity of analyzing and designing cyber–physical systems and enables their plug-and-play into networked operations. 相似文献
120.
《Expert systems with applications》2014,41(10):4670-4679
Failure mode and effects analysis (FMEA) is a widely used risk assessment tool for defining, identifying and eliminating potential failures or problems in products, process, designs and services. Two critical issues of FMEA are the representation and handling of various types of assessments and the determination of risk priorities of failure modes. Many different approaches have been suggested to enhance the performance of traditional FMEA; however, deficiencies exist in these approaches. In this paper, based on a more effective representation of uncertain information, called D numbers, and an improved grey relational analysis method, grey relational projection (GRP), a new risk priority model is proposed for the risk evaluation in FMEA. In the proposed model, the assessment results of risk factors given by FMEA team members are expressed and modeled by D numbers. The GRP method is used to determine the risk priority order of the failure modes that have been identified. Finally, an illustrative case is provided to demonstrate the effectiveness and practicality of the proposed model. 相似文献