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Application of Series Formula Method in Optimization Arrangement of Webs
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作者 Qiaozhi Sang Siwen Li +1 位作者 Shuqi Wang Dianxuan Gong 《World Journal of Engineering and Technology》 2018年第3期651-660,共10页
The expressions of the internal forces of the webs under the vertical loads of the simply supported beam type trusses with vertical and horizontal webs and without vertical webs are studied through the mathematical fo... The expressions of the internal forces of the webs under the vertical loads of the simply supported beam type trusses with vertical and horizontal webs and without vertical webs are studied through the mathematical formula method. The variations of internal forces under different angles and spacings of the webs are simulated. The law of the optimal arrangement of the webs of the parallel-string simple-beam truss is obtained: under the condition that the rigidity of the rod is allowed, the form of no vertical web-type truss and reducing the span distance and inclination of the side span are advisable, which can save materials and reduce the weight as well. This method can be applied to the calculation of internal forces for arbitrary loads and truss forms. 展开更多
关键词 SERIES formula method BEAM TRUSS OPTIMUM Arrangement of WEBS
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Recursion-transform method and potential formulae of the m×n cobweb and fan networks 被引量:12
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作者 谭志中 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第9期82-90,共9页
In this paper, we made a new breakthrough, which proposes a new recursion–transform(RT) method with potential parameters to evaluate the nodal potential in arbitrary resistor networks. For the first time, we found ... In this paper, we made a new breakthrough, which proposes a new recursion–transform(RT) method with potential parameters to evaluate the nodal potential in arbitrary resistor networks. For the first time, we found the exact potential formulae of arbitrary m × n cobweb and fan networks by the RT method, and the potential formulae of infinite and semi-infinite networks are derived. As applications, a series of interesting corollaries of potential formulae are given by using the general formula, the equivalent resistance formula is deduced by using the potential formula, and we find a new trigonometric identity by comparing two equivalence results with different forms. 展开更多
关键词 recursion-transform method network model potential formula exact solution
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A GENERALIZED GAUSS-TYPE QUADRATURE FORMULA AND ITS APPLICATIONS TO PSEUDOSPECTRAL METHOD
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作者 王立联 郭本瑜 王中庆 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2002年第2期179-196,共18页
A generalized Gauss-type quadrature formula is introduced, which assists in selection of collocation points in pseudospectral method for differential equations with two-point derivative boundary conditions. Some resul... A generalized Gauss-type quadrature formula is introduced, which assists in selection of collocation points in pseudospectral method for differential equations with two-point derivative boundary conditions. Some results on the related Jacobi interpolation are established. A pseudospectral scheme is proposed for the Kuramoto-Sivashisky equation. A skew symmetric decomposition is used for dealing with the nonlinear convection term. The stability and convergence of the proposed scheme are proved. The error estimates are obtained. Numerical results show the efficiency of this approach. 展开更多
关键词 GENERALIZED Gauss-type QUADRATURE formula PSEUDOSPECTRAL method K-S equa-tion.
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The Convergences Comparison between the Halley’s Method and Its Extended One Based on Formulas Derivation and Numerical Calculations
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作者 Shunji Horiguchi 《Applied Mathematics》 2016年第18期2394-2410,共17页
The purpose of this paper is that we give an extension of Halley’s method (Section 2), and the formulas to compare the convergences of the Halley’s method and extended one (Section 3). For extension of Halley’s met... The purpose of this paper is that we give an extension of Halley’s method (Section 2), and the formulas to compare the convergences of the Halley’s method and extended one (Section 3). For extension of Halley’s method we give definition of function by variable transformation in Section 1. In Section 4 we do the numerical calculations of Halley’s method and extended one for elementary functions, compare these convergences, and confirm the theory. Under certain conditions we can confirm that the extended Halley’s method has better convergence or better approximation than Halley’s method. 展开更多
关键词 Recurrence formula Newton’s method Halley’s method Extension of Halley’s method Third-Order Convergence
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Formula calculation methods of water content in sweet natural gas and their adaptability analysis
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作者 Zhu Lin Fan Junming +2 位作者 Zhu Jia Qin Li Li Luling 《Natural Gas Industry B》 2014年第2期144-149,共6页
Estimation of water content is the foundation of natural gas processing and designing,and a formula calculation method provides a solution simple and easy to be programmed by computers.In this regard,several main form... Estimation of water content is the foundation of natural gas processing and designing,and a formula calculation method provides a solution simple and easy to be programmed by computers.In this regard,several main formula calculation methods of water content in sweet natural gas were reviewed and evaluated individually.There are formulas fitted with nomographic data(e.g.Sloan formula,Ning Yingnan formula,Khaled formula and Bahadori formula),empirical formulas fitted with experimental data(e.g.Zhu Lin formula,Behr formula and Kazim formula)and formulas generated based on water-hydrocarbon phases equilibrium(e.g.Saturated Vapor Pressure Model,Modified Ideal Model,Simplified Thermodynamic Model and Bukacek formula).The comparison of calculated and experimental values of each above formula calculation method indicates that,the Khaled formula provided the minimum average absolute deviation(AAD)–2.5240%,while the Behr method achieved the maximum AAD–19.255%.After the analysis of the AAD results calculated by the methods at different temperature ranges,the Zhu Lin formula is recommended for−50 to−40℃,the Sloan formula for−40 to 0℃,the Simplified Thermodynamic Model for 0 to 37.78°C,the Khaled formula for 37.78 to 171.11℃,and the Bukacek formula for 171.11 to 237.78℃. 展开更多
关键词 Natural gas Sweet natural gas Water content formula calculation method Average absolute deviation(AAD) Evaluation method
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A Nonstationary Halley’s Iteration Method by Using Divided Differences Formula
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作者 Nasr Al Din Ide 《Applied Mathematics》 2012年第2期169-171,共3页
This paper presents a new nonstationary iterative method for solving non linear algebraic equations that does not require the use of any derivative. The study uses only the Newton’s divided differences of first and s... This paper presents a new nonstationary iterative method for solving non linear algebraic equations that does not require the use of any derivative. The study uses only the Newton’s divided differences of first and second orders instead of the derivatives of (1). 展开更多
关键词 NONSTATIONARY ITERATIVE method Hally’s formula Divided DIFFERENCES
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On Relations between the General Recurrence Formula of the Extension of Murase-Newton’s Method (the Extension of Tsuchikura*-Horiguchi’s Method) and Horner’s Method
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作者 Shunji Horiguchi 《Applied Mathematics》 2014年第4期777-783,共7页
In 1673, Yoshimasu Murase made a cubic equation to obtain the thickness of a hearth. He introduced two kinds of recurrence formulas of square and the deformation (Ref.[1]). We find that the three formulas lead to the ... In 1673, Yoshimasu Murase made a cubic equation to obtain the thickness of a hearth. He introduced two kinds of recurrence formulas of square and the deformation (Ref.[1]). We find that the three formulas lead to the extension of Newton-Raphson’s method and Horner’s method at the same time. This shows originality of Japanese native mathematics (Wasan) in the Edo era (1600- 1867). Suzuki (Ref.[2]) estimates Murase to be a rare mathematician in not only the history of Wasan but also the history of mathematics in the world. Section 1 introduces Murase’s three solutions of the cubic equation of the hearth. Section 2 explains the Horner’s method. We give the generalization of three formulas and the relation between these formulas and Horner’s method. Section 3 gives definitions of Murase-Newton’s method (Tsuchikura-Horiguchi’s method), general recurrence formula of Murase-Newton’s method (Tsuchikura-Horiguchi’s method), and general recurrence formula of the extension of Murase-Newton’s method (the extension of Tsuchikura-Horiguchi’s method) concerning n-degree polynomial equation. Section 4 is contents of the title of this paper. 展开更多
关键词 RECURRENCE formula Newton-Raphson’s method (Newton’s method) EXTENSIONS of Murase-Newton’s method Horner’s method
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The Formulas to Compare the Convergences of Newton’s Method and the Extended Newton’s Method (Tsuchikura-Horiguchi Method) and the Numerical Calculations
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作者 Shunji Horiguchi 《Applied Mathematics》 2016年第1期40-60,共21页
This paper gives the extension of Newton’s method, and a variety of formulas to compare the convergences for the extension of Newton’s method (Section 4). Section 5 gives the numerical calculations. Section 1 introd... This paper gives the extension of Newton’s method, and a variety of formulas to compare the convergences for the extension of Newton’s method (Section 4). Section 5 gives the numerical calculations. Section 1 introduces the three formulas obtained from the cubic equation of a hearth by Murase (Ref. [1]). We find that Murase’s three formulas lead to a Horner’s method (Ref. [2]) and extension of a Newton’s method (2009) at the same time. This shows originality of Wasan (mathematics developed in Japan) in the Edo era (1603-1868). Suzuki (Ref. [3]) estimates Murase to be a rare mathematician in not only the history of Wasan but also the history of mathematics in the world. Section 2 gives the relations between Newton’s method, Horner’s method and Murase’s three formulas. Section 3 gives a new function defined such as . 展开更多
关键词 Recurrence formula Newton-Raphson’s method (Newton’s method) Extension of Newton’s method
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Precise integration methods based on the Chebyshev polynomial of the first kind 被引量:2
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作者 Wang Mengfu F. T. K. Au 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2008年第2期207-216,共10页
This paper introduces two new types of precise integration methods based on Chebyshev polynomial of the first kind for dynamic response analysis of structures, namely the integral formula method (IFM) and the homoge... This paper introduces two new types of precise integration methods based on Chebyshev polynomial of the first kind for dynamic response analysis of structures, namely the integral formula method (IFM) and the homogenized initial system method (HISM). In both methods, nonlinear variable loadings within time intervals are simulated using Chebyshev polynomials of the first kind before a direct integration is performed. Developed on the basis of the integral formula, the recurrence relationship of the integral computation suggested in this paper is combined with the Crout decomposed method to solve linear algebraic equations. In this way, the IFM based on Chebyshev polynomial of the first kind is constructed. Transforming the non-homogenous initial system to the homogeneous dynamic system, and developing a special scheme without dimensional expansion, the HISM based on Chebyshev polynomial of the first kind is able to avoid the matrix inversion operation. The accuracy of the time integration schemes is examined and compared with other commonly used schemes, and it is shown that a greater accuracy as well as less time consuming can be achieved. Two numerical examples are presented to demonstrate the applicability of these new methods. 展开更多
关键词 structural dynamics Chebyshev polynomial of the first kind the Crout decomposed method integral formula method homogenized initial system method
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倾斜不规则工作面开采沉陷预计模型的构建与实现
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作者 赵春苏 陈俊杰 闫伟涛 《河南理工大学学报(自然科学版)》 北大核心 2026年第2期204-212,共9页
目的为提升复杂开采条件下地表移动变形预计精度,准确预测倾斜不规则工作面开采引起的地表移动与变形。方法基于采深变化的单元影响函数,提出倾斜煤层任意开采单元采深计算方法,并构建适用于倾斜不规则工作面的沉陷预计模型。该模型利... 目的为提升复杂开采条件下地表移动变形预计精度,准确预测倾斜不规则工作面开采引起的地表移动与变形。方法基于采深变化的单元影响函数,提出倾斜煤层任意开采单元采深计算方法,并构建适用于倾斜不规则工作面的沉陷预计模型。该模型利用格林公式将沉陷面积分转化为边界线积分,推导了相应的线积分预计公式,并给出数值求解方法。在此基础上,开发了一体化预计程序,实现了从参数输入、积分区间确定到线积分求解的全流程计算,能够输出地表下沉、倾斜、曲率、水平移动和水平变形等预计结果的可视化,评价分析工作面采动损害的等级,并结合实际矿区倾斜工作面开采实例,对所构建的预计模型进行验证与分析。结果结果表明,提出的倾斜不规则工作面开采移动变形预计模型和一体化程序,能够有效解决复杂开采条件下地表沉陷的精确预测计算和采动损害等级划分,预计结果符合开采沉陷基本规律,预计下沉的相对误差小于10%,满足工程预计的精度要求。结论预计模型具有可靠性和实用性,预计精度高,可为倾斜不规则工作面矿山开采优化设计和地表损害精准评估与防护对策制定提供理论依据和技术支撑。 展开更多
关键词 开采沉陷预计 不规则工作面 倾斜煤层 概率积分法 格林公式
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Box-Behnken响应面法优化补肾益脑方提取工艺及其对阿尔茨海默病的作用评估
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作者 赵子越 邹烨 +4 位作者 刘阿娇 高萌 孟祥鹤 李学涛 于洋 《广州化工》 2026年第2期60-66,共7页
以多糖和人参皂苷提取量为考察指标,采用Box-Behnken法优化补肾益脑方提取工艺,并评估其对D-半乳糖诱导的阿尔茨海默病模型小鼠的疗效。结果显示,最佳提取工艺为加水10倍,提取3次,每次2 h,多糖含量为(5.84±0.062)mg/mL,人参皂苷含... 以多糖和人参皂苷提取量为考察指标,采用Box-Behnken法优化补肾益脑方提取工艺,并评估其对D-半乳糖诱导的阿尔茨海默病模型小鼠的疗效。结果显示,最佳提取工艺为加水10倍,提取3次,每次2 h,多糖含量为(5.84±0.062)mg/mL,人参皂苷含量为(2.31±0.015)mg/mL。动物实验表明,补肾益脑方可显著改善模型小鼠的学习与认知能力,降低脑内氧化应激和神经炎症水平,减少神经元损伤。优化工艺操作简便、准确,具有良好的预测性和重现性,为补肾益脑方的进一步研究提供了实验依据。 展开更多
关键词 补肾益脑 响应面法 处方优选 阿尔茨海默病 药效评价
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张喜奎教授辨治痛风经验浅析
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作者 付国群 张喜奎 范秋梦 《中医药学报》 2026年第1期58-61,共4页
本文旨在介绍张喜奎教授辨治痛风经验,其在痛风发作期,投以白虎加桂枝汤,佐入清热利湿、凉血解毒、通利关节之品;在痛风缓解期,投以补气通络方,佐入化痰行瘀、通阳凉营、散结开络、健脾益肾之品。另外,依痛势及病程,灵活合用芍药甘草汤... 本文旨在介绍张喜奎教授辨治痛风经验,其在痛风发作期,投以白虎加桂枝汤,佐入清热利湿、凉血解毒、通利关节之品;在痛风缓解期,投以补气通络方,佐入化痰行瘀、通阳凉营、散结开络、健脾益肾之品。另外,依痛势及病程,灵活合用芍药甘草汤;根据热、湿、痰、瘀、虚之轻重,调整治法及用药;并强调药当守恒,重视生活调摄。 展开更多
关键词 痛风 辨证论治 化裁诸法
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瞬时单位线法与推理公式法对调洪库容差异的影响
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作者 骆欢 罗金 《吉林水利》 2026年第2期46-50,共5页
为对比瞬时单位线法与推理公式法在水库调洪计算中的适用性,以CS水库为研究对象,基于其气象水文资料及流域特征,采用2种方法在考虑和不考虑下游小型水库调洪能力的工况下计算设计洪水,并进行调洪库容分析。结果表明:推理公式法计算的洪... 为对比瞬时单位线法与推理公式法在水库调洪计算中的适用性,以CS水库为研究对象,基于其气象水文资料及流域特征,采用2种方法在考虑和不考虑下游小型水库调洪能力的工况下计算设计洪水,并进行调洪库容分析。结果表明:推理公式法计算的洪峰流量普遍高于瞬时单位线法(工况一高10%~15%,工况二高8%~12%);不考虑已建水库调蓄(工况二)的入库洪峰更大(1000年一遇流量达579.49m^(3)/s)。 展开更多
关键词 调洪计算 瞬时单位线法 推理公式法 洪峰流量
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建筑建造阶段碳排放计算方法比较研究
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作者 江祯蓉 《建筑经济》 2026年第3期52-59,共8页
本文根据国家及地方标准对建造阶段碳排放计算方法的规定,梳理出四种建造阶段碳排放计算方法,并对计算方法的数据来源难易度、计算精度、适用场景进行对比分析。结合案例开展不同计算方法的碳排放计算,对比计算结果得出,比值估算法(取... 本文根据国家及地方标准对建造阶段碳排放计算方法的规定,梳理出四种建造阶段碳排放计算方法,并对计算方法的数据来源难易度、计算精度、适用场景进行对比分析。结合案例开展不同计算方法的碳排放计算,对比计算结果得出,比值估算法(取建材阶段10%)、施工能耗定额估算法、施工工序能耗计算法计算结果均在合理范围内,适用于建造阶段碳排放计算。比值估算法计算结果和实际数据计算结果偏差最小且计算快速,可优先用于碳排放计算。 展开更多
关键词 建造碳排放 经验公式法 比值估算法 施工能耗定额估算法 施工工序能耗计算法
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共同富裕目标下企业所得税汇总合并纳税制度的重构
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作者 姚子健 罗亚飞 《税务与经济》 北大核心 2026年第1期29-38,共10页
我国现行企业所得税横向分配制度特别是汇总合并纳税规则存在显著缺陷,其为人为税收筹划和不合理区域间利益转移提供了空间,加剧了“税收与税源背离”。为此,应在确立共同富裕发展目标的基础上,对我国企业所得税汇总合并纳税制度进行系... 我国现行企业所得税横向分配制度特别是汇总合并纳税规则存在显著缺陷,其为人为税收筹划和不合理区域间利益转移提供了空间,加剧了“税收与税源背离”。为此,应在确立共同富裕发展目标的基础上,对我国企业所得税汇总合并纳税制度进行系统性优化。在汇总纳税制度层面,取消非居民企业汇总纳税选择权及主要机构、场所的条件限制,加强制度刚性;在合并纳税制度层面,明确合并纳税原理及目标,构建普适、规范、可控的合并纳税制度,增加不同区域间企业的关联,实现共同富裕。在此基础上,使区域间企业所得税公式分配法更加科学化,能够在各区域均衡合理地分配企业所得税利益。 展开更多
关键词 企业所得税 利益横向分配 共同富裕 汇总纳税 合并纳税 公式分配法
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益气活血法治疗高流量型阴茎异常勃起二例及文献复习
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作者 李家诚 舒渊源 +2 位作者 刘耿 洪嘉宝 黄晓军 《罕少疾病杂志》 2026年第2期5-7,共3页
目的研究动脉介入造影高选择性栓塞病变血管治疗高流量型阴茎异常勃起及益气活血法对于术后康复的实际疗效。方法回顾性分析2例动脉介入造影高选择性栓塞病变血管治疗高流量型阴茎异常勃起的诊断和治疗经过以及益气活血法对患者术后康... 目的研究动脉介入造影高选择性栓塞病变血管治疗高流量型阴茎异常勃起及益气活血法对于术后康复的实际疗效。方法回顾性分析2例动脉介入造影高选择性栓塞病变血管治疗高流量型阴茎异常勃起的诊断和治疗经过以及益气活血法对患者术后康复治疗的随访情况。结果两例患者均在动脉造影过程中行高选择性动脉弹簧圈栓塞,异常勃起症状消失。术后予益气活血法治疗后勃起功能存在,勃起状态稳定。结论动脉介入造影高选择性栓塞病变血管治疗高流量型阴茎异常勃起安全有效,益气活血法对于术后康复疗效显著,为中西医结合治疗该病提供帮助。 展开更多
关键词 阴茎异常勃起 动脉介入造影 弹簧圈栓塞 益气活血法 红景Ⅰ号方
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经典名方茯苓桂枝甘草大枣汤古今文献考证
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作者 张傲 陈心语 +2 位作者 王兴杰 颜秉硕 殷寻嫣 《河南中医》 2026年第1期67-76,共10页
目的:考证茯苓桂枝甘草大枣汤源流演变,确证其方源、组成、剂量、炮制、煎服法及主治等关键信息,为其传承与标准化应用奠定基础。方法:古代文献分析:采用文献计量学方法,系统检索古籍,运用历史比较、版本校勘、训诂考据等方法,结合多重... 目的:考证茯苓桂枝甘草大枣汤源流演变,确证其方源、组成、剂量、炮制、煎服法及主治等关键信息,为其传承与标准化应用奠定基础。方法:古代文献分析:采用文献计量学方法,系统检索古籍,运用历史比较、版本校勘、训诂考据等方法,结合多重质控与证据分级,对方剂源流、异名演变、医家注解、药物组成、剂量折算、炮制规范、煎服细节及主治病症进行系统考证与量化分析。现代文献分析:依托中国知网与万方数据平台,以“茯苓桂枝甘草大枣汤”“临床”“医案”“疗效”为主题词进行检索,时间跨度为1983年1月至2025年7月。结果:本方源流清晰,出自东汉张仲景所著《伤寒论》,药物组成茯苓、桂枝、甘草、大枣在全部考证医籍中完全一致。以宋本《伤寒论》为基准,明确原方剂量为茯苓半斤折125 g,桂枝四两折62.5 g,甘草二两折31.25 g,大枣十五枚折45 g;规范炮制要求为桂枝去粗皮、甘草蜜炙、茯苓净制去筋、大枣擘破;煎服法为甘澜水2000 mL,先煮茯苓至1600 mL,后纳余药煮取600 mL,温服200 mL,每日3次。核心主治界定为发汗后脐下悸动、气欲上冲,此记载占考证文献主流,历代医家对相关症状延伸或兼症补充均未脱离此核心病症范畴。现代文献分析:共纳入有效文献20篇,大多聚焦于所治“奔豚病”,近年来应用本方治疗他病有所增多,如治疗脾胃系疾病之呃逆等。结论:茯苓桂枝甘草大枣汤各项关键信息明确,为该经典名方准确传承、标准化应用及现代研究与拓展提供了文献学依据。 展开更多
关键词 茯苓桂枝甘草大枣汤 文献考证 文献计量学 方剂源流 剂量 炮制 煎服法 主治病症 经典名方 《伤寒论》 张仲景
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牛油火锅底料配方优化和挥发性风味物质分析
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作者 李波 段秀峰 +6 位作者 史凯文 于洋 徐炜桢 李苗苗 王建洲 刘胜 祝贺 《中国调味品》 北大核心 2026年第1期179-188,共10页
该研究以糍粑辣椒添加量、麻椒添加量和复合香料添加量作为火锅底料配方优化的关键变量,基于单因素试验结果,采用响应面法对配方进行多因素优化,通过感官评价确定最佳工艺参数。同时,采用固相微萃取法提取火锅底料中的挥发性物质,结合... 该研究以糍粑辣椒添加量、麻椒添加量和复合香料添加量作为火锅底料配方优化的关键变量,基于单因素试验结果,采用响应面法对配方进行多因素优化,通过感官评价确定最佳工艺参数。同时,采用固相微萃取法提取火锅底料中的挥发性物质,结合气相色谱-质谱联用技术与相对气味活度值(ROAV)分析方法,系统解析其风味物质组成特征。研究结果表明,当糍粑辣椒添加量9.8%、麻椒添加量2.7%、复合香料添加量1.6%时具有较佳的感官评分。采用气相色谱-质谱联用技术(GC-MS)对响应面法优化后的火锅底料挥发性风味物质进行分析,主要风味物质为醇类和烃类。此外,还含有少量醚类、酮类、酯类、醛类、酚类、酸类和其他类物质,ROAV分析结果表明,牛油火锅底料关键风味物质是芳樟醇和D-柠檬烯,桉叶油醇、β-水芹烯、β-蒎烯、蒎烯、α-水芹烯、丁香酚、茴香脑等物质对牛油火锅底料的总体风味均起到重要的修饰作用。 展开更多
关键词 火锅底料 感官评分 配方优化 挥发性物质 响应面法
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婴幼儿配方乳粉中水分存在形式及状态研究
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作者 孙忱 李斯林 +5 位作者 仝润喆 熊丽娜 刘少莉 雷霆 何光华 王博 《中国乳品工业》 北大核心 2026年第1期25-30,73,共7页
婴幼儿配方乳粉中水分的存在形式及状态与脂肪氧化、蛋白质变性、结块等特性密切相关。文章利用低场核磁共振法和卡尔费休·库伦法对3种婴幼儿配方乳粉中水分存在形式及状态进行探究。结果表明,用低场核磁共振法根据弛豫时间测得婴... 婴幼儿配方乳粉中水分的存在形式及状态与脂肪氧化、蛋白质变性、结块等特性密切相关。文章利用低场核磁共振法和卡尔费休·库伦法对3种婴幼儿配方乳粉中水分存在形式及状态进行探究。结果表明,用低场核磁共振法根据弛豫时间测得婴幼儿配方乳粉样品中束缚水、不易流动水和自由水占比分别为2.9%±0.8%、96.6%±0.8%和0.4%±0.2%;利用卡尔费休·库伦法升温程序测得婴幼儿配方乳粉中游离水和结合水释放温度分别为75℃和120℃,利用库伦法恒温程序测得婴幼儿配方乳粉样品中游离水和结合水的含量分别为1.19%±0.07%和1.70%±0.02%;通过对3种乳粉样品进行干燥失水处理(75℃,30 min),再用低场核磁共振法和卡尔费休·库伦法对乳粉样品中水分存在的形式及状态进行检测,发现低场核磁共振法测得乳粉样品中束缚水含量无显著变化,不易流动水含量显著下降,自由水含量显著增加,库伦法测得结合水含量不变,游离水含量减少87.9%±0.8%。本试验利用2种不同测定方法分别阐明婴幼儿配方乳粉中水分的存在形式和状态及变化规律,为进一步研究婴幼儿配方乳粉中水分与产品质量的关系提供理论依据,对精确控制婴幼儿配方乳粉的营养和物理性质具有一定指导意义。 展开更多
关键词 婴幼儿配方乳粉 低场核磁共振法 卡尔费休·库伦法 水分存在形式
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An explicit method for numerical simulation of wave equations 被引量:3
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作者 Liu Heng Liao Zhenpeng 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第1期17-28,共12页
In this paper, a method to develop a hierarchy of explicit recursion formulas for numerical simulation in an irregular grid for scalar wave equations is presented and its accuracy is illustrated via 2-D and 1-D models... In this paper, a method to develop a hierarchy of explicit recursion formulas for numerical simulation in an irregular grid for scalar wave equations is presented and its accuracy is illustrated via 2-D and 1-D models. Approaches to develop the stable formulas which are of 2M-order accuracy in both time and space with Mbeing a positive integer for regular grids are discussed and illustrated by constructing the second order (M= 1) and the fourth order (M = 2) recursion formulas. 展开更多
关键词 wave equation numerical simulation explicit recursion formula finite element method
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