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1.
中国的海相富有机质页岩经历了多期构造改造,其含气性具有明显的差异。页岩气在不同构造演化阶段的保存条件是揭示页岩气差异富集机理的关键科学问题之一,开展构造-热演化研究可以明确其热演化史和构造隆升-剥蚀过程,为其评价提供演化格架。研究以丁山地区下古生界页岩为对象,联合磷灰石裂变径迹、磷灰石(U-Th)/He和锆石(U-Th)/He等多个古温标反演热演化史,结合镜质体反射率重建的最高古地温剖面,对丁山地区燕山期以来的差异构造隆升过程和剥蚀量进行了恢复,并在此基础上结合流体包裹体分析对丁山地区龙马溪组页岩的压力演化过程进行了模拟;根据页岩在埋藏—抬升过程中的温、压演化特征,定量表征了不同抬升阶段页岩含气量的变化,建立了龙马溪组页岩"埋藏—生烃—抬升"的演化格架。分析表明,丁山地区在燕山期和喜马拉雅期经历了不同的构造隆升过程。燕山期表现为"早期快速隆升—晚期缓慢隆升"的分段隆升,具有自NW向SE递进隆升且隆升幅度逐渐增大的特征;喜马拉雅期表现为整体快速隆升。燕山期是丁山地区产生差异构造隆升的主要时期。受这种差异构造隆升-剥蚀作用的影响,龙马溪组页岩的降温、降压过程和页岩气的散失过程具有明显的差异。燕山期的差异构造隆升是造成丁山地区龙马溪组页岩含气性呈平面分带的主要原因。 相似文献
2.
研究湿法氧化锌种类和用量对天然橡胶(NR)性能的影响。结果表明:与添加普通氧化锌的胶料相比,对于未填充炭黑NR体系,减半用量的湿法氧化锌混炼胶的焦烧时间和t90较短,Fmax较大;硫化胶的定伸应力、拉伸强度和剪切模量(G′)较大,拉断伸长率、损耗模量(G″)和损耗因子(tanδ)较小。对于填充炭黑NR体系,减半用量的湿法氧化锌混炼胶的门尼粘度、G′和G″较大,tanδ较小,焦烧时间和t90较短,Fmax较大;硫化胶的密度稍低,硬度和定伸应力较大,耐老化性能较好,玻璃化温度较低,tanδ较小,其他物理性能变化不大。湿法氧化锌FF的性能优于湿法氧化锌HR。 相似文献
3.
为了研究缓蚀剂组分及添加条件对发射药性的影响,设计并制备了一种含新型有机硅的缓蚀剂材料;采用烧蚀管法,对比石蜡+TiO2型缓蚀剂,研究了新型有机硅缓蚀剂的静态降烧蚀效果;采用密闭爆发器研究了不同缓蚀剂添加条件对高能硝胺发射药点火和燃烧性能的影响;采用14.5mm弹道枪和壁温测试装置,研究不同缓蚀剂添加条件对膛壁温度、内弹道性能和枪口烟雾的影响。结果表明,采用含新型有机硅的缓蚀剂,降烧蚀效果更为显著;随着缓蚀剂添加量的增加,压力峰值、弹丸初速也会产生小幅下降,但总体影响幅度较小;添加缓蚀剂后,射击过程膛壁峰值温度显著下降,下降幅度随着缓蚀剂添加量的增加而增加,在缓蚀剂质量分数为3%时,对身管壁温降低幅度可达17.1%,且产生的枪口烟雾量较少;在缓蚀剂质量分数为5%时,缓蚀剂添加过量,枪口产生较大烟雾。该缓蚀剂及添加条件有望应用于低烧蚀发射药配方中。 相似文献
4.
In the present paper, the refrigerant mixture R32/R290 (68%/32% by weight) is investigated as the drop-in replacement for R410A in household air conditioners. The GWP of it is only 22% of that of R410A. Theoretical and experimental investigations are conducted on the performance of the air conditioners working with both R32/R290 and R410A. Experimental results show that the refrigerant charge amount of R32/R290 is reduced by 30.0%–35.0%; the cooling and heating capacities are increased by 14.0%–23.7%. For further reducing charge amount and flammability, the micro-channel heat exchanger (condenser) is employed to replace the finned tube one. Compared with the R32/R290 system using finned tube heat exchanger, the R32/R290 charge amount and the power consumption are reduced by 34.1% and 0.4%, respectively; the cooling capacity and the COP are increased by 6.4% and 6.8%, respectively. 相似文献
5.
Differential evolution (DE) is a simple and powerful evolutionary algorithm for global optimization. DE with constraint handling techniques, named constrained differential evolution (CDE), can be used to solve constrained optimization problems (COPs). In existing CDEs, the parents are randomly selected from the current population to produce trial vectors. However, individuals with fitness and diversity information should have more chances to be selected. This study proposes a new CDE framework that uses nondominated sorting mutation operator based on fitness and diversity information, named MS-CDE. In MS-CDE, firstly, the fitness of each individual in the population is calculated according to the current population situation. Secondly, individuals in the current population are ranked according to their fitness and diversity contribution. Lastly, parents in the mutation operators are selected in proportion to their rankings based on fitness and diversity. Thus, promising individuals with better fitness and diversity are more likely to be selected as parents. The MS-CDE framework can be applied to most CDE variants. In this study, the framework is applied to two popular representative CDE variants, (μ + λ)-CDE and ECHT-DE. Experiment results on 24 benchmark functions from CEC’2006 and 18 benchmark functions from CEC’2010 show that the proposed framework is an effective approach to enhance the performance of CDE algorithms. 相似文献
6.
为实现钱家营矿掘进工作面煤与瓦斯突出实时预警,提出一种基于瓦斯涌出特征的预警方法。依据巷道高低浓度甲烷传感器实时监测数据,通过离散回归理论分析煤与瓦斯突出前的瓦斯涌出量,建立预警指标特征序列,确定掘进工作面煤与瓦斯突出预警指标危险临界值:方差0.018,波峰差0.41,波动斜率±0.027。在此基础上构建了非接触式煤与瓦斯突出可视化预警系统并在钱家营矿进行现场应用。结果表明,以瓦斯涌出特征值作为预警指标,能够准确监测到井下瓦斯异常现象,达到瓦斯数据实时解算和可视化预警的目的,为钱家营矿掘进工作面防突工作提供技术借鉴。 相似文献
7.
在COB(Chip On Board)LED光组件制造领域,点胶、测试和补粉关键工艺基本以手工或半自动为主。为了保证COB LED产品质量一致性、提高生产效率,研制了一种COB自动在线点胶测试及补粉一体机,实现点胶、测试、补粉生产工序的自动化生产。阐述了其工艺流程及设计总体方案,提出了荧光粉量修补方法,修正初次点胶量,实现动态调节,减少人工干预。经实验验证,该一体机可以提高点胶工艺的自动化程度,具有运行速度快、可靠性好、性能稳定等特点。 相似文献
8.
9.
《International Journal of Hydrogen Energy》2021,46(69):34381-34388
Estimation of hydrogen production rate and the total amount hydrogen during any reaction process require an accurate and concise dynamic model to describe the variation of hydrogen production rate with reaction time. There must be two comprehensive features of such model, the first one is that the hydrogen production rate calculated by this model is zero at the initial time is zero and the second one is that the integration of this model over time result in an explicit function. In this paper, we present a comprehensive model which meets above two requirements via amendments to the shifted logistic model. The model is validated against measured results through comparison of 25 experimental and theoretical hydrogen production rate. The experimentally validated model is used to calculate the total amount hydrogen during each reaction process. The impact of some experimental conditions on the total hydrogen production was mathematically explained for the first time, and this result reveal the excellent predictive ability of framework suggested in this paper. In addition, that is for an experimental condition history, predictions are achieved by developing a set of “secondary models” that describe some experimental conditions dependence of the “primary models” parameters. The method to obtain the parameters in “secondary models” described in this paper indicated that another major departure from the conventional models is the notion that the “secondary models” do not need to follow any preconceived formula and that they can be derived solely from the observed growth patterns. The presented framework can help the hydrogen production industry. 相似文献
10.
样品采用固相萃取小柱净化,以C18色谱柱为分离柱,以甲酸水—乙腈为流动相进行梯度洗脱,经LC-MS/MS检测,以多反应监测模式检测目标化合物的特征离子进行定性定量分析。结果表明:该方法线性范围为0.1~10.0μg/mL,线性相关系数0.999 0,方法的检出限为0.01mg/kg,定量限为0.03mg/kg。在加标水平为0.03,0.10,0.50 mg/kg时,方法的回收率为88.3%~95.2%,RSD在4.5%~8.8%。该方法前处理方式简便、有机溶剂用量少、分析时间短、选择性好且灵敏度高,适用于番茄和黄瓜中敌菌灵的检测。 相似文献