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A UNIVERSAL ANALYTIC POTENTIAL-ENERGY FUNCTION BASED ON A PHASE FACTOR 被引量:11
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作者 CFYu KYan DZLiu 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2006年第6期455-468,共14页
Using a field equation with a phase factor, a universal analytic potential-energy function applied to the interactions between diatoms or molecules is derived, and five kinds of potential curves of common shapes are o... Using a field equation with a phase factor, a universal analytic potential-energy function applied to the interactions between diatoms or molecules is derived, and five kinds of potential curves of common shapes are obtained adjusting the phase factors. The linear thermal expansion coefficients and Young's moduli of eleven kinds of face-centered cubic (fcc) metals - Al, Cu, Ag, etc. are calculated using the potential-energy function; the computational results are quite consistent with experimental values. Moreover, an analytic relation between the linear thermal expansion coefficients and Young's moduli of fcc metals is given using the potential-energy function. Finally, the force constants of fifty-five kinds of diatomic moleculars with low excitation state are computed using this theory, and they are quite consistent with RKR (Rydberg-Klein-Rees) experimental values. 展开更多
关键词 universal potential energy function field equation phase factor derivative renormalization linear thermal expansion coefficient Young's modulus force constant
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Low-complexity PTS scheme based on phase factor sequences optimization 被引量:2
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作者 JI Ce ZHANG Chao ZHU Wenjing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第4期707-713,共7页
In this paper, a new partial transmit sequence(PTS)scheme with low computational complexity is proposed for the problems of high computational complexity in the conventional PTS method. By analyzing the relationship... In this paper, a new partial transmit sequence(PTS)scheme with low computational complexity is proposed for the problems of high computational complexity in the conventional PTS method. By analyzing the relationship of candidate sequences in the PTS method under the interleaved partition method, it has been discovered that some candidate sequences generated by phase factor sequences have the same peak average power ratio(PAPR). Hence, phase factor sequences can be optimized to reduce their searching times. Then, the computational process of generating candidate sequences can be simplified by improving the utilization of data and minimizing the calculations of complex multiplication. The performance analysis shows that, compared with the conventional PTS scheme, the proposed approach significantly decreases the computational complexity and has no loss of PAPR performance. 展开更多
关键词 partial transmit sequence (PTS) peak average powerratio (PAPR) phase factor sequences optimization orthogonal frequency division multiplexing (OFDM) low computational com-plexity
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Diagnostic usefulness of selected proteases and acute phase factors in patients with colorectal adenocarcinoma
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作者 Tadeusz Sebzda Jan Gnus +2 位作者 Barbara Dziadkowiec Miroslaw Latka Jakub Gburek 《World Journal of Gastroenterology》 SCIE CAS 2021年第39期6673-6688,共16页
BACKGROUND Uncontrolled growth and loss of control over basic metabolic functions,leading to invasive proliferation and metastases,are the salient traits of malignant tumors in general and colorectal cancer in particu... BACKGROUND Uncontrolled growth and loss of control over basic metabolic functions,leading to invasive proliferation and metastases,are the salient traits of malignant tumors in general and colorectal cancer in particular.Invasion and metastases hinder effective tumor treatment.While surgical techniques and radiotherapy can be used to remove tumor focus,only chemotherapy can eliminate dispersed neoplastic cells.However,the efficacy of the latter method is limited in the advanced stages of the disease.Therefore,recognition of the mechanisms involved in neoplastic cell spreading is indispensable for developing effective therapies.AIM To use a number of biomarkers involved in cancer progression and identify a panel that could be used for effective early diagnosis.METHODS We recruited 185 patients with colorectal adenocarcinoma(98 men,87 women with median age 63).Thirty-five healthy controls were sex and age-matched.Dukes’staging was as follows:A=22,B=52,C=72,D=39.We analyzed patients'blood serum before surgery.We determined:(1)Cathepsin B(CB)with Barrett's method(fluorogenic substrate);(2)Leukocytic elastase(LE)in a complex with alpha 1 trypsin inhibitor(AAT)using the immunoenzymatic MERCK test;(3)Total sialic acid(TSA)with the colorimetric periodate-resorcinol method;(4)Lipid-bound sialic acid(LASA)with the colorimetric Taut's method;and(5)The antitrypsin activity(ATA)employing the colorimetric test.RESULTS In patients,the values of the five biochemical parameters were as follows:CB=16.1±8.8 mU/L,LE=875±598μg/L,TSA=99±31 mg%,LASA=0.68±0.33 mg%,and ATA=3211±1504 U/mL.Except for LASA,they were significantly greater than those of controls:CB=11.4±6.5 mU/L,LE=379±187μg/L,TSA=71.4±15.1 mg%,LASA=0.69±0.28 mg%,and ATA=2016±690 U/mL.For CB and LASA,the differences between the four Dukes’stages and controls were not statistically significant.The inter-stage differences for CB and LASA were also absent.The receiver operating characteristic(ROC)analysis revealed the potential diagnostic value of CB,TSA,and ATA.The area under ROC,sensitivity,and specificity for these three parameters were:0.85,72%,90%;0.75,66%,77%;and 0.77,63%,84%,respectively.The sensitivity and specificity for the threeparameter panel CB-TSA-ATA were equal to 88.2%and 100%,respectively.CONCLUSION The increased value of CB,TSA,and ATA parameters are associated with tumor biology,invasion,and metastasis of colorectal cancer.The presented evidence suggests the potential value of the CB-TSA-ATA biochemical marker panel in early diagnostics. 展开更多
关键词 Colorectal cancer Cathepsin B Acute phase reactants Colorectal adenocarcinoma Acute phase factor
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Beyond the Dirac Phase Factor: Dynamical Quantum Phase-Nonlocalities in the Schrödinger Picture
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作者 Konstantinos Moulopoulos 《Journal of Modern Physics》 2011年第11期1250-1271,共22页
Generalized solutions of the standard gauge transformation equations are presented and discussed in physical terms. They go beyond the usual Dirac phase factors and they exhibit nonlocal quantal behavior, with the wel... Generalized solutions of the standard gauge transformation equations are presented and discussed in physical terms. They go beyond the usual Dirac phase factors and they exhibit nonlocal quantal behavior, with the well-known Relativistic Causality of classical fields affecting directly the phases of wavefunctions in the Schr?dinger Picture. These nonlocal phase behaviors, apparently overlooked in path-integral approaches, give a natural account of the dynamical nonlocality character of the various (even static) Aharonov-Bohm phenomena, while at the same time they seem to respect Causality. For particles passing through nonvanishing magnetic or electric fields they lead to cancellations of Aharonov-Bohm phases at the observation point, generalizing earlier semiclassical experimental observations (of Werner & Brill) to delocalized (spread-out) quantum states. This leads to a correction of previously unnoticed sign-errors in the literature, and to a natural explanation of the deeper reason why certain time-dependent semiclassical arguments are consistent with static results in purely quantal Aharonov-Bohm configurations. These nonlocalities also provide a remedy for misleading results propagating in the literature (concerning an uncritical use of Dirac phase factors, that persists since the time of Feynman’s work on path integrals). They are shown to conspire in such a way as to exactly cancel the instantaneous Aharonov-Bohm phase and recover Relativistic Causality in earlier “paradoxes” (such as the van Kampen thought-experiment), and to also complete Peshkin’s discussion of the electric Aharonov-Bohm effect in a causal manner. The present formulation offers a direct way to address time-dependent single- vs double-slit experiments and the associated causal issues—issues that have recently attracted attention, with respect to the inability of current theories to address them. 展开更多
关键词 AHARONOV-BOHM GAUGE TRANSFORMATIONS DIRAC phase factor Quantum phases
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Non-Abelian Berry phase Factor of the Degenerate states
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作者 Wang Jianbo Shanxi Teacher’s University 《山西师范大学学报(自然科学版)》 1991年第4期30-35,共6页
Suppose the degenerate states wave function of a Hamitonian operatorHis accompanied by a natural phase factor, then we can own it to the role of sometransformation generator played by some non--degenerate Hermitian op... Suppose the degenerate states wave function of a Hamitonian operatorHis accompanied by a natural phase factor, then we can own it to the role of sometransformation generator played by some non--degenerate Hermitian operator containedin the complete set of conserved mechanical quantities. When this idea is extended tothe spece coordinated by parameters and the momentum--like operator is introduced,thenon-Abelian Berry phose factor of degenerate wave function can be easily gotter afterthe system evolves along a closed adiabatic curve. 展开更多
关键词 Degnerate STATE Non-Abelian BERRY phase factor
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Bainite isothermal transformation of Si–Mn–Mo alloy by phase structure factor calculation under different rare earth contents 被引量:1
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作者 Yan-Liang Yi Yi-Long Liang Qi-Bing Tan 《Rare Metals》 SCIE EI CAS CSCD 2014年第4期427-432,共6页
The effect of rare earth (RE) on bainite trans- formation mechanism is not yet unified in the academia. Therefore, further studying the effect of RE on bainite transformation mechanism will have important guiding si... The effect of rare earth (RE) on bainite trans- formation mechanism is not yet unified in the academia. Therefore, further studying the effect of RE on bainite transformation mechanism will have important guiding significance for the development of bainite steels. In this paper, using differential dilatometer (DIL805A/D), heat treatment was performed and C-curve was drawn. The effect of phase structure factor on bainite transformation under two different fractions of RE in Si-Mn-Mo bainite steels was investigated by the empirical electron theory (EET) of solids, molecules, dilatometry, and metallogra- phy. Experimental results show that RE makes Fe-C- RE segregation structural unit of Si-Mn-Mo bainite steels increase, i.e., the values of phase structure factor (na, FDC) increase, and delay bainite transformation due to the drag effect resulting from the segregation of RE ferrite island interphase and the retardation of RE to carbon diffusion in Si-Mn-Mo bainite steels. Beside this, C-curve is shifted to right and down, and microstructures of bainite ferrite and substructures are finer. 展开更多
关键词 phase structure factor C-CURVE SUBSTRUCTURE Rare earths
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Influencing factors for catalytic oxidation of mine gas to methanol in liquid phase 被引量:2
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作者 ZHU Lihua XU Feng +1 位作者 BI Yewu SHEN Bin 《Chinese Journal Of Geochemistry》 EI CAS CSCD 2014年第2期183-186,共4页
The influencing factors for liquid phase catalytic oxidation of mine gas to methanol(in form of CH3COOCH3) are studied using the self-established experimental apparatus. The results show that CH3COOCH3(target product)... The influencing factors for liquid phase catalytic oxidation of mine gas to methanol(in form of CH3COOCH3) are studied using the self-established experimental apparatus. The results show that CH3COOCH3(target product) is obtained by using CH3COOH as reaction solvent, and the yield of target product increases with the increasing of reaction temperature, gas pressure and reaction time. In the mine gas-Pd(OAc)2-CH3COOH system, the yield of CH3COOCH3 increases with the increasing of addition of Pd(OAc)2 which is redox catalyst for mine gas conversion. The yield of CH3COOCH3 will be greatly improved by composite additional oxidant which is obtained by equimolar mix of p-benzoquinone with NO2. 展开更多
关键词 液相催化氧化 矿井瓦斯 影响因素 甲醇 还原催化剂 实验装置 反应溶剂 反应温度
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DYNAMIC LIE ALGEBRA STRUCTURE OF QUANTAL SYSTEM AND BERRY'S PHASE FACTOR
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作者 孙昌璞 葛墨林 《Chinese Science Bulletin》 SCIE EI CAS 1990年第21期1784-1789,共6页
At present, Berry’s topological phase factor and the studies of its relevant problem have drawn considerable attention . It concerns the theoretical analysis of chiral anomaly, etc., which is also experimentally conf... At present, Berry’s topological phase factor and the studies of its relevant problem have drawn considerable attention . It concerns the theoretical analysis of chiral anomaly, etc., which is also experimentally confirmed. In general, the explicit determination of the 展开更多
关键词 SEMISIMPLE LIE ALGEBRA ADIABATIC approximation Berry’s phase factor.
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一种面向智能移动终端的iPDR/GNSS组合导航方法 被引量:1
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作者 王振杰 胡超 +1 位作者 聂志喜 张远帆 《中国惯性技术学报》 北大核心 2025年第1期55-63,69,共10页
针对现有行人航位推算(PDR)方法存在误差积累并且定位与航向精度较低,从而导致PDR/全球导航卫星系统(GNSS)组合导航精度下降的问题,提出了一种面向智能移动终端的改进的PDR(iPDR)/GNSS组合导航方法。首先,设计了一种iPDR定位方法,将GNS... 针对现有行人航位推算(PDR)方法存在误差积累并且定位与航向精度较低,从而导致PDR/全球导航卫星系统(GNSS)组合导航精度下降的问题,提出了一种面向智能移动终端的改进的PDR(iPDR)/GNSS组合导航方法。首先,设计了一种iPDR定位方法,将GNSS载波相位历元差分技术计算的航向角引入PDR航向估计中,减小由陀螺漂移引起的航向累积误差。其次,基于因子图优化将GNSS绝对位置与iPDR定位结果相融合。最后,利用智能手机采集的实测数据对所提方法进行验证。实验结果表明:与传统PDR方法相比,iPDR方法的定位精度提高了62.0%,航向精度提高了33.7%;与基于卡尔曼滤波的iPDR/GNSS组合方法相比,基于因子图优化的iPDR/GNSS方法在定位精度上提高了39.8%,有效提高了组合导航系统的精度。 展开更多
关键词 改进行人航位推算 组合导航 智能移动终端 载波相位差分 因子图优化
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敏感肺结核患者强化期痰培养延迟阴转的危险因素分析 被引量:1
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作者 史珂 代金芳 李强 《合肥医科大学学报》 2025年第3期274-279,285,共7页
目的 探讨影响敏感肺TB患者强化期痰培养阴转延迟的危险因素。方法 纳入自2020年6月至2024年6月在北京胸科医院经痰液培养确诊的肺TB患者567例,根据2月末时痰培养阴转情况分为阴转组和未阴转组,采用Logistic回归模型分析患者强化期痰培... 目的 探讨影响敏感肺TB患者强化期痰培养阴转延迟的危险因素。方法 纳入自2020年6月至2024年6月在北京胸科医院经痰液培养确诊的肺TB患者567例,根据2月末时痰培养阴转情况分为阴转组和未阴转组,采用Logistic回归模型分析患者强化期痰培养延迟阴转的危险因素。结果 强化期结束时痰培养转阴组423例(74.6%),未阴转组144例(25.4%),多因素Logistic回归分析结果显示,年龄≥60岁[OR(95%CI):3.092(2.383~4.947),P=0.029]、男性[3.062(1.717~5.460),P<0.001]、有吸烟史[1.904(1.071~3.386),P=0.028]、有饮酒史[1.934(1.095~3.416),P=0.023]、合并糖尿病[2.585(1.587~4.209),P<0.001]、肺部空洞≥2个[2.543(1.497~4.321),P=0.001]、累及肺野数≥4个[3.880(1.614~9.326),P=0.002]是强化期痰培养阴转延迟的危险因素。结论 临床上,对于具备以上危险因素的患者,采取相应措施进行干预,可适当延长强化期治疗时间。 展开更多
关键词 肺结核 强化期 培养 危险因素
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高强双相钢U形翻边回弹规律的研究与分析 被引量:1
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作者 刘洋 刘辉 +3 位作者 史晓强 穆孟春 张通 赵启扬 《山西冶金》 2025年第3期53-55,共3页
高强双相钢在板料冲压成形的过程中存在材料回弹的情况,它会影响冲压零部件的尺寸精度和外观形状,并在整装装配过程中出现一系列问题。选取不同厚度的590DP、780DP材料对双相钢翻边回弹的特点进行研究,得到结论:对同一钢种进行不同厚度... 高强双相钢在板料冲压成形的过程中存在材料回弹的情况,它会影响冲压零部件的尺寸精度和外观形状,并在整装装配过程中出现一系列问题。选取不同厚度的590DP、780DP材料对双相钢翻边回弹的特点进行研究,得到结论:对同一钢种进行不同厚度的翻边回弹实验时,基本呈现出厚度越大、回弹越小的规律;590DP的θ2回弹随着翻边角度的增加呈现升高趋势,780DP的θ2回弹随着翻边角度的变化基本不变,各钢种的θ1回弹随着翻边角度增加均呈降低趋势;相比而言,θ1回弹对翻边角度变化较为敏感。 展开更多
关键词 高强双相钢 翻边回弹 影响因素
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基于“脉息-运气-经典方”辨治皮肤病思路探讨
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作者 张益琳 孙淑娜 +5 位作者 王龙艳 孙中华 张子晨 纪云 王冬阳 张晓杰 《中华中医药杂志》 北大核心 2025年第1期253-256,共4页
皮肤病种类繁多,病程缠绵,对患者生理、心理都有较大影响。张晓杰教授以阴阳为纲,遵循天人相应,重视脉诊,善用“脉息-运气-经典方”思路。以脉息辨少气、平人、脉躁,结合五运六气理论,从平调脏腑、启玄府调津液、调腠理和营卫角度,运用... 皮肤病种类繁多,病程缠绵,对患者生理、心理都有较大影响。张晓杰教授以阴阳为纲,遵循天人相应,重视脉诊,善用“脉息-运气-经典方”思路。以脉息辨少气、平人、脉躁,结合五运六气理论,从平调脏腑、启玄府调津液、调腠理和营卫角度,运用经典方辨治皮肤病,疗效显著,对临床治疗有参考和借鉴意义。 展开更多
关键词 皮肤病 脉息 五运六气 经典方 辨治 思路
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光电二极管放大电路的SPICE仿真与实验研究
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作者 丛梦龙 周昆鹏 《现代电子技术》 北大核心 2025年第16期19-24,共6页
为整体提升光电二极管放大电路性能,在理论研究基础上,结合软件仿真和实验测试对设计方案加以优化。首先从系统传递函数角度出发,揭示引发电路振荡的原因,即开环增益和反馈因子之间特定幅度和相位关系。在此基础上,利用TINA SPICE交流... 为整体提升光电二极管放大电路性能,在理论研究基础上,结合软件仿真和实验测试对设计方案加以优化。首先从系统传递函数角度出发,揭示引发电路振荡的原因,即开环增益和反馈因子之间特定幅度和相位关系。在此基础上,利用TINA SPICE交流和瞬态仿真功能,以图解方式直观阐明振荡条件,并给出用于相位补偿的反馈电容取值不同时所测得的环路增益波特图,以及系统频率响应、阶跃响应和脉冲响应。对比上述仿真结果,讨论反馈电容对系统稳定性和带宽的影响,并进一步考虑稳定性和带宽,计算出补偿电容的理想取值。针对因电容过小而在应用中难以实现的问题,提出以T型阻容网络等效小电容的策略,并通过仿真加以验证。最后,对系统相位裕度和带宽进行了实验测试。结果表明,当补偿电容为5 pF时,相位裕度约为68.4°,过冲优于8%,未见振铃现象。 展开更多
关键词 光电二极管 开环增益 TINA SPICE 反馈因子 环路增益 相位裕度
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不同来源沉香精油中关键气味化合物的分析
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作者 冯伟 何萍 +2 位作者 冯晓丽 杨水莲 梅小虎 《林业工程学报》 北大核心 2025年第4期78-86,共9页
为了比较海南奇楠沉香精油、印尼沉香精油、绿奇楠沉香精油、奇楠沉香精油中关键气味化合物的差异,本研究通过气相-质谱/质谱(GC-MS/MS)和气相-质谱-嗅闻(GC-MS-O)法分析气味化合物的组成。实验结果表明,GC-MS/MS共检测54种气味化合物,... 为了比较海南奇楠沉香精油、印尼沉香精油、绿奇楠沉香精油、奇楠沉香精油中关键气味化合物的差异,本研究通过气相-质谱/质谱(GC-MS/MS)和气相-质谱-嗅闻(GC-MS-O)法分析气味化合物的组成。实验结果表明,GC-MS/MS共检测54种气味化合物,包括4种单萜、42种倍半萜类、2种醛类、3种酮类、3种其他类。其中有26种气味化合物可以被GC-MS-O识别,其香气稀释因子(FD)的范围为1~243。海南奇楠沉香精油中特征气味化合物主要是β-榄香烯(FD=243)和α-檀香醇(FD=243);印尼沉香精油以β-榄香烯(FD=81)、γ-桉叶油醇(FD=81)和α-檀香醇(FD=81)为主;绿奇楠沉香精油中以α-愈创木烯(FD=243)、(E)-α-佛手甘油烯(FD=81)、γ-杜松烯(FD=81)为主;而奇楠沉香精油中以γ-摩勒烯(FD=27)和γ-芹子烯(FD=27)为主。此外,结合电子鼻和化学计量法可以将4种不同来源的沉香精油进行区分。综上可知,不同沉香精油中气味化合物的差异赋予其独特的气味属性,但海南奇楠沉香精油和绿奇楠沉香精油的气味很接近。 展开更多
关键词 沉香精油 固相微萃取 香气稀释因子 倍半萜 电子鼻
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深层致密砂岩微观孔喉结构对气水相渗的控制机理
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作者 周露 卓勤功 +5 位作者 罗翔 公言杰 成友友 胡旭 王锦洲 章国威 《科学技术与工程》 北大核心 2025年第1期128-136,共9页
深层致密砂岩储层的孔隙结构复杂、非均质性强,孔隙微观参数对气水相渗特征的影响因素难以确定。以分形几何理论为基础,结合岩心压汞法、核磁共振T2谱测试及微米CT扫描结果获取了储层微观孔喉参数及各尺度分形维数,通过可动气体孔隙度... 深层致密砂岩储层的孔隙结构复杂、非均质性强,孔隙微观参数对气水相渗特征的影响因素难以确定。以分形几何理论为基础,结合岩心压汞法、核磁共振T2谱测试及微米CT扫描结果获取了储层微观孔喉参数及各尺度分形维数,通过可动气体孔隙度和最大气相相对渗透率,讨论了分形维数、微观孔喉结构参数对气水相渗特征的控制机理。结果表明,压汞和核磁共振分形曲线具有明显的“三段式”特征,且储层总分形维数描述气水共存时渗流及可动流体分布状况更精细;最大进汞饱和度、平均孔喉半径、储层总分形维数及排驱压力对气体渗流时的可动气体孔隙度影响较为显著;平均孔喉半径对气体渗流时的最大有效气相相对渗透率影响较为显著。在明确微观孔喉结构对气水相渗的控制机理后,可以为产水气藏高效开发提供有力指导。 展开更多
关键词 深层致密砂岩 分形维数 微观孔喉 影响因素 气水相渗特征
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基于五运六气学说运用正阳汤验案举隅
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作者 崔海兰 朱婷婷 李凤鸣 《山东中医杂志》 2025年第8期927-930,共4页
正阳汤出自宋代陈无择的《三因极一病证方论》,是针对子午之岁少阴君火司天、阳明燥金在泉的运气特点所创之方,具有“辛温以和其寒、酸苦以泄其热”的功效,临床用于治疗燥火合邪所致的各类疾病,取得良好效果。本文列举4则典型验案(烦躁... 正阳汤出自宋代陈无择的《三因极一病证方论》,是针对子午之岁少阴君火司天、阳明燥金在泉的运气特点所创之方,具有“辛温以和其寒、酸苦以泄其热”的功效,临床用于治疗燥火合邪所致的各类疾病,取得良好效果。本文列举4则典型验案(烦躁恶心案、特应性皮炎案、尘肺案、外阴瘙痒案)以分析探讨。 展开更多
关键词 司天运气方 正阳汤 燥火合邪 五运六气 烦躁恶心 特应性皮炎 尘肺 外阴瘙痒
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基于密集线性台阵地震被动源成像的渭河盆地西缘精细沉积结构研究
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作者 徐勇 邓宝 +4 位作者 田晓峰 倪红玉 段永红 肖本夫 李俊伦 《地质学报》 北大核心 2025年第5期1508-1522,共15页
为研究渭河盆地西缘强震风险重点区域的地下精细结构和沉积特征,本研究布设了一条由平均台站间距200 m、共254个短周期三分量节点式地震仪组成的密集线性台阵,进行了为期30天的连续地震数据采集。我们首先计算了背景噪声垂直分量的互相... 为研究渭河盆地西缘强震风险重点区域的地下精细结构和沉积特征,本研究布设了一条由平均台站间距200 m、共254个短周期三分量节点式地震仪组成的密集线性台阵,进行了为期30天的连续地震数据采集。我们首先计算了背景噪声垂直分量的互相关,应用近期发展的拓距相移法提取了3 Hz~3.3 s的基阶瑞利面波频散曲线,进而反演得到测线下方2.5 km以浅的高分辨率横波速度结构。此外,利用采集到的三分量背景噪声数据,采用单台噪声谱比法(HVSR)计算峰值频率,根据经验公式估计了渭河盆地沉积层厚度。背景噪声成像获得的二维横波速度剖面呈现出高速—低速—高速的横向变化特征,与典型沉积盆地隆起—坳陷—隆起的地质结构吻合,清晰刻画了区域内3条主控断裂和2个地质构造单元,与地震主动源反射剖面结果一致;HVSR成像结果揭示了研究区域内沉积层较厚,层序明显,新生界的古近系、新近系和第四系的地层层序发育完整;结合背景噪声成像、HVSR和已有主动源地震反射剖面等资料,综合研究表明测线下方存在的3条主控断裂在该区域均未穿透第四系。本研究表明背景噪声拓距相移法和HVSR方法结合在沉积盆地结构探测中具有良好的实际应用效果,为沉积盆地结构探测提供了新的技术方法和途径。 展开更多
关键词 渭河盆地 沉积结构 背景噪声成像 拓距相移法 场地放大效应
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脑卒中患者康复期决策参与偏好现状及其影响因素的研究
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作者 梅永霞 赛一溥 +6 位作者 徐盼盼 刘亚婷 刘志薇 张思训 石忆楠 樊宝钰 张杜杜 《军事护理》 北大核心 2025年第9期10-13,共4页
目的探讨脑卒中患者康复期决策参与偏好的现状及其影响因素,为临床制订针对性干预措施提供依据。方法2023年12月至2024年3月,采用便利抽样选取郑州市3所三级甲等医院神经内科收治的305例脑卒中患者为研究对象,采用一般资料调查量表、维... 目的探讨脑卒中患者康复期决策参与偏好的现状及其影响因素,为临床制订针对性干预措施提供依据。方法2023年12月至2024年3月,采用便利抽样选取郑州市3所三级甲等医院神经内科收治的305例脑卒中患者为研究对象,采用一般资料调查量表、维克森林医师信任量表(Wick forest physician trust scale,WFPTS)、决策参与偏好评估量表(control preferences scale,CPS)、社会支持评定量表(social support rating scale,SSRS)及全面健康素养测量量表(all aspects of health literacy scale,AAHLS)对其进行调查。结果脑卒中患者康复期决策参与偏好倾向于共享型的有156例(51.15%)、倾向于被动型的有104例(34.10%)、倾向于主动型的有45例(14.75%)。Logistic回归分析显示,文化程度、对疾病了解程度、医疗支付形式、医生信任、社会支持及健康素养是脑卒中患者康复期决策参与偏好的主要影响因素(均P<0.05)。结论脑卒中患者康复期决策参与偏好存在异质性,医护人员应结合影响因素调整策略,助力患者主动参与决策,提高治愈率。 展开更多
关键词 脑卒中 康复期 决策参与偏好 影响因素
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Binary Phase Shaping and SHG Contrast Ratios
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作者 Tingyao Xiong 《Journal of Applied Mathematics and Physics》 2024年第8期3026-3035,共10页
Finding binary sequences with Large SHG ratios is very important in the field of ultrafast science, biomedical optics, high-resolution microscopy and label-free imaging. In this paper, we have demonstrated the relatio... Finding binary sequences with Large SHG ratios is very important in the field of ultrafast science, biomedical optics, high-resolution microscopy and label-free imaging. In this paper, we have demonstrated the relation between the SHG contrast ratio and the traditional Merit Factor values. And in the light from known results in Merit Factor Problems, we have shown that Legendre Sequences or Jacobi Sequences, are still the best candidates to obtain binary sequences with large SHG contrast ratios. The authors also discussed the SHG behaviors on some sequences obtained from cyclotomic classes over the finite field GF (2l) . 展开更多
关键词 Binary phase Shaping Binary Sequences SHG Contrast Ratio Merit factor
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两种可用于描述晶粒变形传递倾向性的物理量:滑移位向差和孪生取向差
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作者 赵子博 王清江 +2 位作者 刘建荣 刘玉敬 杨锐 《聊城大学学报(自然科学版)》 2025年第5期703-706,共4页
变形在晶粒间传递方式直接主导了材料的力学行为。作者基于变形在晶粒间的传递现象,提出了描述晶粒间变形传递倾向性的物理量:滑移位向差和孪生取向差。阐述了两物理量的概念、公式及其关键推导过程。该物理量可更直观地表述多变形模式... 变形在晶粒间传递方式直接主导了材料的力学行为。作者基于变形在晶粒间的传递现象,提出了描述晶粒间变形传递倾向性的物理量:滑移位向差和孪生取向差。阐述了两物理量的概念、公式及其关键推导过程。该物理量可更直观地表述多变形模式下的变形传递行为,便于统计性分析和预测,为多晶材料的塑性变形研究提供新的分析工具。 展开更多
关键词 变形传递 几何相容因子 滑移位向差 孪生取向差 相变取向差
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