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Photoacoustic treatment mitigates cognitive dysfunction in a model of sleep-wake rhythm disturbance 预览
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作者 Fang Xing Xin Fang +5 位作者 Xiang-Dan Gong Xin Zhao Ying Du Zheng-Liang Ma Xiao-Ping Gu Tian-Jiao Xia 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第6期1094-1101,共8页
Sleep-wake rhythm disturbances,which are characterized by abnormal sleep timing or duration,are associated with cognitive dysfunction.Photoacoustic treatments including light and sound stimulation have been found to b... Sleep-wake rhythm disturbances,which are characterized by abnormal sleep timing or duration,are associated with cognitive dysfunction.Photoacoustic treatments including light and sound stimulation have been found to be effective in modulating sleep patterns and improving cognitive behavior in abnormal sleep-wake pattern experiments.In this study,we examined whether light and sound interventions could reduce sleep-wake pattern disturbances and memory deficits in a sleep rhythm disturbance model.We established a model of sleep rhythm disturbance in C57 BL/6 J mice via a sleep deprivation method involving manual cage tapping,cage jostling,and nest disturbance.We used a Mini Mitter radio transmitter device to monitor motor activity in the mice and fear conditioning tests to assess cognitive function.Our results indicated that an intervention in which the mice were exposed to blue light(40-Hz flickering frequency)for 1 hour during their subjective daytime significantly improved the 24-hour-acrophase shift and reduced the degree of memory deficit induced by sleep deprivation.However,interventions in which the mice were exposed to a 40-Hz blue light at offset time or subjective night time points,as well as 2 Hz-blue light at 3 intervention time points(subjective day time,subjective night time,and offset time points),had no positive effects on circadian rhythm shift or memory deficits.Additionally,a 2000-Hz sound intervention during subjective day time attenuated the24-hour-acrophase shift and memory decline,while 440-Hz and 4000-Hz sounds had no effect on circadian rhythms.Overall,these results demonstrate that photoacoustic treatment effectively corrected abnormal sleep-wake patterns and cognitive dysfunction associated with sleep-deprivation-induced disturbances in sleep-wake rhythm.All animal experiments were approved by the Experimental Animal Ethics Committee of Drum Tower Hospital Affiliated to the Medical College of Nanjing University,China(approval No.20171102)on November20,2017. 展开更多
关键词 circadian rhythm cognitive impairment fear conditioning light intervention photoacoustic treatment rhythm disturbance rhythm shift sleep deprivation sleep-wake rhythm sound intervention
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Shift in Subtitling—Taking Desperate Housewives as an Example 预览
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作者 张垚 《海外英语》 2019年第12期62-63,共2页
This article mainly focuses on one significant translation technique—shift.Through the analysis from seven aspects,it comes to the conclusion that although subtitling has some restrictions,it still has rules to follow.
关键词 SUBTITLE TRANSLATION DESPERATE Housewives SHIFT
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党的第二次工作重心转移的历史经验研究 预览
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作者 刘暖 《西安建筑科技大学学报:社会科学版》 2019年第4期21-26,共6页
党的工作重心的转移也即是党在一定历史时期内的工作重点和工作方向的转变。中国共产党的历史即将走向百年,党在近百年的历史征程中有几次工作重心的转移,党在七届二中全会上做出了实现第二次转移的决定,即把工作重心由农村转向城市,党... 党的工作重心的转移也即是党在一定历史时期内的工作重点和工作方向的转变。中国共产党的历史即将走向百年,党在近百年的历史征程中有几次工作重心的转移,党在七届二中全会上做出了实现第二次转移的决定,即把工作重心由农村转向城市,党的第二次工作重心的转移形成了若干历史经验,研究这些成功的历史经验对当下中国共产党加强自身建设,提升党的工作水平,提高党的长期执政能力具有十分重要的意义。 展开更多
关键词 中国共产党 工作重心 转移 历史经验
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Efficient catalytic hydrogen generation by intermetallic platinum-lead nanostructures with highly tunable porous feature
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作者 Bin E Lingzheng Bu +2 位作者 Qi Shao Yujing Li Xiaoqing Huang 《科学通报:英文版》 SCIE EI CSCD 2019年第1期36-43,共8页
The water-gas shift (WGS)reaction is an essential industrial reaction for upgrading hydrogen (H2)by removing carbon monoxide (CO),while highly efficient platinum (Pt)-based catalysts for WGS with simultaneously high a... The water-gas shift (WGS)reaction is an essential industrial reaction for upgrading hydrogen (H2)by removing carbon monoxide (CO),while highly efficient platinum (Pt)-based catalysts for WGS with simultaneously high activity and stability are still yet to be developed due to the poisoning issue during the reaction.Herein,we report on the porous PtPb peanut nanocrystals (porous PtPb PNCs)and porous PtPb octahedron nanocrystals (porous PtPb ONCs)with controllable ratios of Pt/Pb as extremely active and stable catalysts towards WGS reaction.It exhibits the composition-dependent activity with porous PtPb PNCs-40/ZnO being the most active for WGS to H2,16.9 times higher than that of the commercial Pt/C.The porous PtPb PNCs-40/ZnO also display outstanding durability with barely activity decay and negligible structure and composition changes after ten successive reaction cycles.X-ray photoelectron spectroscopy (XPS)results reveal that the suitable binding energy of Pt 4f7/12 and the high ratio of Pt(0) to Pt(Ⅱ)in porous PtPb PNCs/Zn0 and porous PtPb ONCs/ZnO are crucial for the enhanced WGS activity. The CO stripping results indicate the optimized CO adsorption strength on the Pt surface ensure the excellent WGS activity and the outstanding durability.The present work demonstrates an important advance in tuning the porous metal nanomaterials as highly efficient and durable catalysts for catalysis, energy conversion and beyond. 展开更多
关键词 POROUS Selective ETCHING Hydrogen Pt-Pb Water-gas shift
Formulation of Determining the Gravity Potential Difference Using Ultra-High Precise Clocks via Optical Fiber Frequency Transfer Technique
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作者 Ziyu Shen Wen-Bin Shen +3 位作者 Zhao Peng Tao Liu Shougang Zhang Dingbo Chao 《地球科学学刊:英文版》 SCIE CAS CSCD 2019年第2期422-428,共7页
Based on gravity frequency shift effect predicted by general relativity theory, this study discusses an approach for determining the gravity potential(geopotential) difference between arbitrary two points P and Q by r... Based on gravity frequency shift effect predicted by general relativity theory, this study discusses an approach for determining the gravity potential(geopotential) difference between arbitrary two points P and Q by remote comparison of two precise optical clocks via optical fiber frequency transfer. After synchronization, by measuring the signal’s frequency shift based upon the comparison of bidirectional frequency signals from P and Q oscillators connected with two optical atomic clocks via remote optical fiber frequency transfer technique, the geopotential difference between the two points could be determined, and its accuracy depends on the stabilities of the optical clocks and the frequency transfer comparison technique. Due to the fact that the present stability of optical clocks achieves 1.6×10-18 and the present frequency transfer comparison via optical fiber provides stabilities as high as 10-19 level, this approach is prospective to determine geopotential difference with an equivalent accuracy of 1.5 cm. In addition, since points P and Q are quite arbitrary, this approach may provide an alternative way to determine the geopotential over a continent, and prospective potential to unify a regional height datum system. 展开更多
关键词 GRAVITY FREQUENCY shift OPTICAL fiber FREQUENCY TRANSFER OPTICAL CLOCK GRAVITY potential
轮值夜班中年女性护士压力源分析及对策探讨 预览
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作者 陈静 《中国继续医学教育》 2019年第12期190-192,共3页
目的探讨轮值夜班中年女性护士的压力源,对其进行分析,并采取积极应对措施。方法选择2017年3—10月某三甲医院40周岁以上轮值夜班女性护士52例作为研究对象。采用症状自评量表(scl-90量化表),通过问卷调查的形式,进行心理状态评估分析,... 目的探讨轮值夜班中年女性护士的压力源,对其进行分析,并采取积极应对措施。方法选择2017年3—10月某三甲医院40周岁以上轮值夜班女性护士52例作为研究对象。采用症状自评量表(scl-90量化表),通过问卷调查的形式,进行心理状态评估分析,对护士进行心理卫生知识培训,使护士学会释放压力,全方位改善护士的身心健康状况;组织瑜伽训练班和各种休闲娱乐活动;进行心理疏导等相应对策进行干预。干预6个月后,进行问卷调查评估。结果干预前后护士心理健康scl-90评分的10项因子结果比较,差异有统计学意义(P<0.05);干预后与常模比较4项因子差异无统计学意义(P>0.05),6项因子差异有统计学意义(P<0.05)。结论采取有效干预措施,可以使中年女性护士获得身心健康。 展开更多
关键词 轮值夜班 中年 女性护士 scl-90量化表 压力 对策
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Spatiotemporal influences of land use/cover changes on the heat island effect in rapid urbanization area
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作者 Ying XIONG Fen PENG Bin ZOU 《地球科学前沿:英文版》 CSCD 2019年第3期614-627,共14页
Rapid urban sprawl and growth led to substantial urban thermal environment changes and influenced the local climate, environment, and quality of life of residents. Taking the Chang-Zhu-Tan urban agglomeration in China... Rapid urban sprawl and growth led to substantial urban thermal environment changes and influenced the local climate, environment, and quality of life of residents. Taking the Chang-Zhu-Tan urban agglomeration in China as a case, this study firstly identified the spatiotemporal patterns of surface urban heat island intensity (SUHII) and the land use/cover changes (LUCC) based on multi-temporal Landsat TM satellite data over 21 years, and then investigated the relationship between LUCC and SUHII by methods of logistic regression model and centroid shift analysis. The results showed that green spaces (e.g., cropland, forestland) of 899.13 km2 had been converted to built-up land during the 1994—2015 period, which caused significant urban expansion. The SUHII was the highest for built-up land, high for unused land, low for cropland and grassland, and the lowest for forestland and open water. Many areas experienced extensive rapid urbanization because of the emergence of the urban agglomeration, which resulted in the loss of green spaces and increased SUHI effects over the 21-year study period. In addition, the results of centroid shift analysis found that the growth of SUHII and the expansion of high SUHII areas are closely related to the expansion of an existing urban area in Xiangtan, while the increases of building density and height in Changsha resulted in the decrease of SUHII and spatiotemporal change of high SUHII areas. The analysis of the effects of land use/cover types on the SUHII in this study will contribute to future urban land use allocation for the mitigation of SUHI formation. 展开更多
关键词 land use/cover change URBANIZATION remote sensing surface urban heat ISLAND intensity CENTROID SHIFT analysis
Spectrum Density Factor of Photons and Its Application in the Casimir Force
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作者 高先龙 孟烨铭 +1 位作者 吴飓昊 汪克林 《理论物理通讯:英文版》 SCIE CAS CSCD 2019年第4期397-402,共6页
The observables of continuous eigenvalues are de?ned in an in?nite-dimensional ket space. The complete set of such eigenstates demands a spectrum density factor, for example, for the photons in the free space and elec... The observables of continuous eigenvalues are de?ned in an in?nite-dimensional ket space. The complete set of such eigenstates demands a spectrum density factor, for example, for the photons in the free space and electrons in the vacuum. From the derivation of the Casimir force without an arti?cial regulator we determine the explicit expression of the spectrum density factor for the photon ?eld to be an exponential function. The undetermined constant in the function is ?xed by the experimental data for the Lamb shift. With that, we predict that there exists a correction to the Casimir force. 展开更多
关键词 SPECTRUM DENSITY FACTOR CASIMIR force Lamb shift
Suppress Blackbody Radiation Shift with Two Clock Ytterbium Clock Transition
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作者 CHENG Jingjing JIANG Kunliang HE Lingxiang 《武汉大学学报:自然科学英文版》 CAS CSCD 2019年第5期427-430,共4页
In order to suppress the blackbody radiation shift of ytterbium(Yb) lattice clock, we adopt the idea of the synthetic frequency by means of the two clock transitions which correspond to the static values of the scalar... In order to suppress the blackbody radiation shift of ytterbium(Yb) lattice clock, we adopt the idea of the synthetic frequency by means of the two clock transitions which correspond to the static values of the scalar and tensor dipole polarizabilities with the AMBiT software package. We have obtained the synthetic wavelength around 647.7 nm and expected when the clock laser is working at the synthetic wavelength, the systematic uncertainty due to the BBR shift can be suppressed at the level of 10–18 or even lower. 展开更多
关键词 BLACKBODY radiation SHIFT CLOCK TRANSITION YTTERBIUM atoms lattice CLOCK
施工碾压推移对沥青面层的影响分析 预览
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作者 杨秋育 《广东公路交通》 2019年第4期60-62,89共4页
施工碾压推移会降低沥青路面的工程质量,引发后期一系列病害。在介绍沥青路面施工病害及影响因素的基础上,结合试验路铺筑与室内试验,从施工碾压推移的过程到影响因素进行了分析,并提出了相关的质量控制措施,以期为相关人员提供借鉴参考。
关键词 沥青路面 施工碾压 推移 质量控制
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塑料超声波点焊技术 预览
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作者 张胜玉 《橡塑技术与装备》 CAS 2019年第16期24-27,共4页
超声波点焊是一种在局部位置连接不带成型孔或导能筋的两热塑性塑料工件的装配方法。超声波点焊产生强固的结构焊缝,适用于大型零件、热塑性挤塑板或铸塑板、热塑性塑料波纹板及有复杂几何形状和难以接近结合面的工件。本文对超声波点... 超声波点焊是一种在局部位置连接不带成型孔或导能筋的两热塑性塑料工件的装配方法。超声波点焊产生强固的结构焊缝,适用于大型零件、热塑性挤塑板或铸塑板、热塑性塑料波纹板及有复杂几何形状和难以接近结合面的工件。本文对超声波点焊原理及机理、点焊适应性、点焊变种、工艺参数、设备要求、特点、应用进行了论述。 展开更多
关键词 超声波点焊 焊头 导向端 径向谐振腔 防揭密封
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Differences between young architects'and non-architects'aesthetic evaluation of buildings
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作者 Katarína Safárová Martin Pírko +2 位作者 Vojtěch Jurík Tomás Pavlica Ondrej Németh 《建筑学研究前沿(英文版)》 CSCD 2019年第2期229-237,共9页
Previous studies showed significant differences between expert architects and laypeople in aesthetic evaluations of buildings.However,studies exploring the aesthetic preferences of architecture students are lacking.Th... Previous studies showed significant differences between expert architects and laypeople in aesthetic evaluations of buildings.However,studies exploring the aesthetic preferences of architecture students are lacking.The present study focused on a population of students and young architects to explore the aesthetic opinion shift within architectural careers.This study was intended to be a conceptual replication of the study of Brown and Gifford(2001)in a Central European context.A total of 109 participants(21-28 years old)evaluated 40 randomized pictures of houses to detect whether non-architecture undergraduates and fresh graduates of architecture would express different aesthetic preferences compared with their peers from the general population.The study also examined whether laypersons can predict the preferences of architects,and vice versa.Results show a trend that is contrary to the original research,that is,young architects and laypeople did not significantly differ in their aesthetic evaluations of the given stimuli.Analyses revealed high prediction ability in young architects and their non-architect peers.Moreover,the existing professional experience of young architects had no influence on the accuracy of their estimations.Findings suggest that the professional shift in architects'expertise is obscured at an early career stage,as revealed in their aesthetic preferences. 展开更多
关键词 ENVIRONMENTAL AESTHETICS AESTHETIC PREFERENCES Building AESTHETICS ENVIRONMENTAL APPERCEPTION Professional opinion shift
核电厂GSS系统疏水箱液位计故障分析及处理 预览
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作者 钱敏 张连强 陶滔 《仪器仪表用户》 2019年第12期45-47,共3页
自方家山机组投入运行以来,每个疏水箱上的3支液位计均存在数值有偏差的情况,尤其是在升功率过程中液位测量偏差较大,对疏水调节控制产生影响。结合GSS系统疏水箱液位调节特点及历史缺陷情况,分析了疏水箱液位计产生数值偏差的原因,提... 自方家山机组投入运行以来,每个疏水箱上的3支液位计均存在数值有偏差的情况,尤其是在升功率过程中液位测量偏差较大,对疏水调节控制产生影响。结合GSS系统疏水箱液位调节特点及历史缺陷情况,分析了疏水箱液位计产生数值偏差的原因,提出更换液位计安装方式的措施,对液位计进行移位设计。改造后运行结果表明,该处理措施初步解决了液位偏差大的问题,保障了机组安全稳定运行。 展开更多
关键词 液位计 偏差 故障 移位
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危重患者实施SBAR标准化床旁交接班模式的设计及应用 预览
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作者 牛建佩 胡少华 +3 位作者 常小霞 刘艳红 白瑞莉 靳冰蕾 《罕少疾病杂志》 2019年第5期88-90,110共4页
目的探讨危重患者实施SBAR模式床旁交接班的设计及应用效果。方法根据综合重症医学科、心血管内科、骨科的专科特点,将交班内容根据SBAR模式进行标准化设计,运用到床旁交接班。分析实施前后护理人员进行病情交班的缺陷情况、护理人员的... 目的探讨危重患者实施SBAR模式床旁交接班的设计及应用效果。方法根据综合重症医学科、心血管内科、骨科的专科特点,将交班内容根据SBAR模式进行标准化设计,运用到床旁交接班。分析实施前后护理人员进行病情交班的缺陷情况、护理人员的满意度,及责任护士对患者病情的掌握情况。结果危重患者运用SBAR模式进行床旁交接班,交班时病情不全的缺陷率由20.3%降低至8.8%(P<0.05),“患者病情掌握”的成绩由实施前的7.8分提高至实施后的9.5分(P<0.05),护士对交班模式满意度为33.43分(满分36分)。结论运用SBAR模式进行床旁交接班,规范危重患者交班流程,减少护理人员病情交班时的信息遗漏,提高护理人员对患者的病情掌握,改进护理工作质量。 展开更多
关键词 SBAR模式 交班 护理 质量改进
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Anomalous SmKS induced by postcritical reflection and refraction at the core-mantle boundary
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作者 Liwei Wang Fenglin Niu 《科学通报:英文版》 SCIE EI CSCD 2019年第21期1601-1607,共7页
Earth’s outer core is generally thought to be a well-mixed liquid consisting mostly of iron and a small amount of lighter elements.Recent seismic studies using Sm KS waves show that the top a few hundred kilometers o... Earth’s outer core is generally thought to be a well-mixed liquid consisting mostly of iron and a small amount of lighter elements.Recent seismic studies using Sm KS waves show that the top a few hundred kilometers of the outer core possess a P-wave velocity slightly lower than the PREM model,which cannot be explained by self-compression of a chemically homogeneous outer core.We investigated the Sm KS waveforms of a deep earthquake occurring beneath South America recorded by a large and dense seismic array in China,and measured the differential arrival times of the Sm KS pairs.We found significant waveform distortion of the Sm KS caused by postcritical refraction and reflection at the core-mantle boundary.This waveform distortion can introduce significant bias to the measured differential times,leading to incorrect estimate of P-wave velocity of the outer core.Whether stable stratification is occurring in outer core or not requires further seismic investigations. 展开更多
关键词 SmKS Hilbert transform Postcritical phase shift Outer-core P-wave velocity Outer core stratification Ultra-low-velocity-zone
Tunable Bistability in the Goos–H?nchen Effect with Nonlinear Graphene
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作者 刘彬彬 马普娟 +2 位作者 於文静 徐亚东 高雷 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第6期33-36,共4页
We present a planar model system of a silica covered with a monolayer of nonlinear graphene to achieve a tunable Goos–H?nchen(GH) shift in the terahertz range. It is theoretically found that the transition between a ... We present a planar model system of a silica covered with a monolayer of nonlinear graphene to achieve a tunable Goos–H?nchen(GH) shift in the terahertz range. It is theoretically found that the transition between a negative shift and a large positive one can be realized by altering the intensity of incident light. Moreover, by controlling the chemical potential of graphene and the incident angle of light, we can further control the tunable GH shift dynamically. Numerical simulations for GH shifts based on Gaussian waves are in good agreement with our theoretical calculations. 展开更多
关键词 GOOS controlling GAUSSIAN SHIFT can our GH It
整函数差分算子的唯一性 预览
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作者 李倩 吴小英 《华南师范大学学报:自然科学版》 CAS 北大核心 2019年第4期108-112,共5页
利用复域差分方程的方法,研究差分多项式的唯一性问题,在某一个整函数具有正的亏值假设下,证明了2个不同整函数的差分算子CM分担某值时的唯一性问题,所得结果可以看作微分情形的差分模拟.
关键词 整函数 位移算子 差分算子 唯一性
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中国传统教育价值观在近代的转变 预览
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作者 郭海洋 《合肥师范学院学报》 2019年第2期1-5,共5页
一个民族的教育思维模式是其民族精神文化素质和智力的集中体现。中国传统教育思维模式作为中华民族文化的教育、心理系统的教育和理论思维能力的基础,在历史上具有重要的影响,尤其是儒家教育模式思维对中国灿烂且封闭的保守的文化思维... 一个民族的教育思维模式是其民族精神文化素质和智力的集中体现。中国传统教育思维模式作为中华民族文化的教育、心理系统的教育和理论思维能力的基础,在历史上具有重要的影响,尤其是儒家教育模式思维对中国灿烂且封闭的保守的文化思维模式具有决定性的影响。中国进入近代后,资本主义后逐渐发展起来,这片古老的土地受到西方文明的强烈冲击,传统教育模式已不能按照过去的轨迹发展,在近代逐渐开始发生转变。 展开更多
关键词 中国传统教育 教育思维模式 中国近代 转变
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煤制甲醇装置中CO变换工艺的优化与应用研究 预览
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作者 谢肥东 《化肥设计》 CAS 2019年第5期44-47,共4页
通过对变换反应机理进行研究,从影响催化剂性能的因素着手,重点对温度、压力、反应物浓度、活性组分等因素,利用反应热力学和动力学原理逐项进行技术分析并确定要因,结合生产实践研究解决催化剂超温的方法,找出了适合工艺控制条件及满... 通过对变换反应机理进行研究,从影响催化剂性能的因素着手,重点对温度、压力、反应物浓度、活性组分等因素,利用反应热力学和动力学原理逐项进行技术分析并确定要因,结合生产实践研究解决催化剂超温的方法,找出了适合工艺控制条件及满足经济效益的最佳方法。 展开更多
关键词 煤制甲醇装置 变换 超温 优化控制
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Role of the dressed and bound states on below-threshold harmonic generation of He atom
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作者 周建伟 焦志宏 +1 位作者 李鹏程 周效信 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第10期192-197,共6页
High-order harmonic generation below ionization threshold of He atom in the laser field is investigated by solving the three-dimensional time-dependent Schrodinger equation. An angular momentum-dependent model potenti... High-order harmonic generation below ionization threshold of He atom in the laser field is investigated by solving the three-dimensional time-dependent Schrodinger equation. An angular momentum-dependent model potential of He atom was used for getting the accurate energy levels of singlet states. The satellite-peak structures of the below-threshold harmonic generation(BTHG) of He are observed. We analyze the emission properties of the BTHG by employing a synchrosqueezing transform technique. We find that the satellite-peak structures have two types related to two kinds of transitions. One is the transition of the dressed states of the excited states, the other is the transition between the excited states and the ground state in the field-free case. Furthermore, our results show that the maximum Stark shift of the 2 p state is about 0.9 Up(penderomotive energy), and that of the 4 p state is about 1.0 Up. It indicates that the energy difference between some satellite-and main-peaks of the BTHG can be used to measure the maximum Stark shift of the excited states of He atom in the laser field. 展开更多
关键词 HARMONIC generation below threshould IONIZATION DRESS state STARK shift
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