自热型熥敷中药镇痛抗炎作用评价及皮肤用药安全性观察

目的考察自热型熥敷中药的有效性及安全性。方法大鼠醋酸扭体实验:将70只SD大鼠根据体质量分为正常对照组、模型对照组、双氯芬酸二乙胺乳胶剂组(0.125 g/次,0.5 h)、传统熥敷中药组(12.42 g/kg,0.5 h)、自热型熥敷中药A(3.06 g/kg,0.5 h)、B(3.06 g/kg,3 h)、C(3.06 g/kg,6 h)组,通过注射醋酸建立大鼠疼痛模型,记录30 min内大鼠扭体的次数和潜伏期,考察自热型熥敷中药镇痛疗效以及与传统熥敷中药对比的疗效差异性;大鼠炎症模型实验:选取20只SD大鼠作为正常对照组和假手术组,60只大鼠腹股沟植入棉球建立炎症模型按体质量随机分为模型对照组、双氯芬酸二乙胺乳胶剂组、传统熥敷中药、自热型熥敷中药A、B、C组(给药剂量、时长同醋酸扭体实验),考察自热型熥敷中药抗炎疗效以及与传统熥敷中药对比的疗效差异性;实验兔皮肤刺激性实验:将8只实验兔分为皮肤完整组以及皮肤受损组,各4只,在左、右两侧分别贴上自热型熥敷中药包及去除药的自热型熥敷中药包。每次6 h,连续使用7 d,在自然光下肉眼观察并记录去除药物后1、24、48 h和72 h敷贴部位有无红斑和水肿等情况;豚鼠斑贴实验:将40只背部经去毛处理无损伤的豚鼠,分为阴性对照组(去除药的自热型熥敷中药包)、阳性对照组(1-氯-2,4-二硝基苯)、供试品组(自热型熥敷中药)。致敏阶段:在第0 d、第7 d和第14 d,观察豚鼠背部左侧给药6 h后1 h、24 h是否出现皮肤刺激性反应,末次致敏14 d后,观察豚鼠右侧给药6 h后24 h、48 h是否出现皮肤刺激性反应。结果自热型熥敷中药B、C组大鼠扭体次数与模型对照组比较,差异有统计学意义(P=0.016、=0.007);传统熥敷中药组与自热型熥敷中药A组大鼠扭体次数比较,差异有统计学意义(P=0.029);双氯芬酸二乙胺组潜伏期与模型对照组比较,差异有统计学意义(P=0.008);自热型熥敷中药C组肉芽肿重量与模型对照组比较,差异有统计学意义(P=0.016)。自热型熥敷中药对皮肤无刺激、无致敏性。结论自热型熥敷中药是具有明显镇痛抗炎作用且安全性较高的新制剂。

自热型方便食品包装加热释放微塑料的情况研究

目的研究分析常见自热型方便食品包装材料中释放微塑料的情况。方法使用激光共聚焦显微镜、扫描电镜、红外拉曼光谱分析仪等实验仪器,检测常见自热速食型的方便食品包装材料在加热过程中释放微塑料颗粒的情况,利用细胞计数板进行微塑料颗粒计数。结果加热后,几种不同类型自热型方便食品包装材料均释放出大量的微塑料,数量从1.94×10^(9)到7.49×10^(9)个/mL,平均释放量为4.21×10^(9)个/mL,包括微米级别和纳米级别塑料。不同品牌方便食品的包装材料在重量、大小和材质上有所差异,因而释放出的微塑料颗粒数量具有一定的差异性,形态为球状、短棒状、条状、片状和不规则形状等,主要材质为聚丙烯(polypropylene,PP)。结论自热型方便食品包装材料在加热过程中会释放出大量的微塑料,对人体健康存在较大风险。该研究结果可为将来食品包装微塑料检测及风险评估提供理论依据和技术参考。

甲醇气相脱水制二甲醚自热型与均温型反应器模拟设计

根据甲醇气相脱水制二甲醚反应的特点，提出自热型与均温型两类新型二甲醚反应器；设计了两类反应器的结构、尺寸、操作条件；考察了反应条件变化对操作结果的影响；将这两类反应器与现用的绝热型反应器进行了比较。

基于自热型酸化提取铜冶炼渣中有价组分铁

本文以铜冶炼渣为研究对象,采用自热型反应,以加工业硫酸酸化、酸浸提取的方法提取有价元素铁。研究考察了液固比、自热反应温度、溶出时间、溶解温度因素对铜冶炼渣中铁溶出的影响规律,以单因素实验为基础,进行正交实验,优化浸提铜冶炼渣中铁的工艺条件。实验结果表明:铜冶炼渣酸浸提取铁的最优工艺条件为:自热反应温度90℃、液固比0.8、溶出时间30 min、溶解温度70℃,此时铁的提取率达到69.95%,通过XRF(X-ray fluorescence spectrometer,X射线荧光光谱分析仪)、SEM(scanning electron microscope,扫描电子显微镜)、XRD(Xray diffraction,X射线衍射仪)、EDS(energy dispersive spectroscopy,能谱仪)等手段对浸取渣的物相和微观形貌进行表征,分析结果表明:铜冶炼渣自热酸浸后,浸取渣中只有SiO_2、少量含铁化合物以及微量Ca SO4存在,说明铜冶炼渣通过自热式酸浸反应可以充分浸取其中的有价组分铁。该法为铜冶炼渣资源化高效利用探索出一条新的工艺思路。

祛瘀散寒方提取物结合自热型贴剂的辅料筛选

目的:优选出祛瘀散寒方提取物结合自热型贴剂的载药层材质,固定敷料贴材质及自发热材料。方法:以剥离舒适性、重复黏贴性、胶体残留量、柔软性、机械强度、色泽外观等感官评价及释热时长、制热温度、载药量、初黏力、持黏力为指标,对该贴剂载药层材质、固定敷料贴材质、发热装置明胶层覆盖率进行筛选。结果:优选的固定敷料贴材质为医用透气无纺布,载药层材质为藻酸盐敷料,40%的明胶层覆盖率可有效控制该发热装置的制热时长及发热温度。结论:筛选得到的固定敷料贴材质、载药层材质质量良好,感官舒适,黏贴性能适宜,可以作为该自热型贴剂的材料,发热装置制热时长及发热温度贴近传统热奄包治疗模式。

稳态自热型对流换热系数传感器研究

为解决旋转固体表面对流换热系数测试难题,设计并研发了一款基于稳态方法的自热型对流换热系数传感器。进行了管道标定实验,分别与经典经验公式以及自制的标定端进行了对比,结果发现传感器的测试存在一个稳定的比例系数,经修正后相对误差小于5%。采用数值模拟方法进一步从机理方面探究了该比例系数存在的合理性,发现在阶跃加热的情况下存在一个"热调整区",会导致对流换热的阶跃性变化,这种变化类似于"入口效应",同时这种效应不受加热段温度的影响,定性地验证了传感器测量的准确性。

Numerical method and model for calculating thermal storage time for an annular tube with phase change material

For calculating the thermal storage time for an annular tube with phase change material （PCM）, a novel method is proposed. The method is suitable for either low-temperature PCM or high-temperature PCM whose initial temperature is near the melting point. The deviation fit is smaller than 8% when the time is below 2x104 s. Comparison between the predictions and the reported experimental data of thermal storage time at same conditions is investigated and good agreements have been got. Based on this method, the performance of the thermal storage unit and the role of natural convection are also investigated. Results show a linear relation between the maximum amount of stored heat and thermal storage time, and their ratio increases with the height of the thermal storage unit. As the thickness of the cavity increases, natural convection plays an increasingly important role in promoting the melting behavior of paraffin. When the thickness of the cavity is small, natural convection restrains the melting behavior of paraffin.

Modeling on dynamic recrystallization of aluminium alloy 7050 during hot compression based on cellular automaton

The dynamic recrystallization(DRX) process of hot compressed aluminium alloy 7050 was predicted using cellular automaton(CA) combined with topology deformation. The hot deformatation characteristics of aluminium alloy 7050 were investigated by hot uniaxial compression tests in order to obtain the material parameters used in the CA model. The influences of process parameters(strain, strain rate and temperature) on the fraction of DRX and the average recrystallization grain(R-grain) size were investigated and discussed. It is found that larger stain, higher temperature and lower strain rate(less than 0.1 s^(–1)) are beneficial to the increasing fraction of DRX. And the deformation temperature affects the mean R-grain size much more greatly than other parameters. It is also noted that there is a critical strain for the occurrence of DRX which is related to strain rate and temperature. In addition, it is shown that the CA model with topology deformation is able to simulate the microstructural evolution and the flow behavior of aluminium alloy 7050 material under various deformation conditions.

CFD modelling of Iongwall goaf gas flow to improve gas capture and prevent goaf self-heating

CFD models have been developed to investigate the Iongwall goaf gas flow patternsunder different mining and geological control conditions.The Iongwall goaf wastreated as porous regions and gas flow was modelled as a momentum sink added to themomentum equation.Gas desorption from the caved goaf and destressed coal seamswithin the mining disturbed area was modelled as additional mass sources in the continuityequation.These CFD models were developed according to specific Iongwall layoutsand calibrated against field monitoring data.Two case studies were presented demonstratingthe application of CFD modelling of goaf gas flow characteristics for improved goafgas capture and the reduction of oxygen ingress into the goaf areas for self-heating prevention.Results from the case studies indicate that the optimum goaf drainage strategywould be a combination of shallow (near the face) and deep holes to improve the overalldrainage efficiency and gas purity.For gassy Iongwall faces retreating against the seam dip,it is recommended to conduct cross-measure roof hole drainage targeting the fracturedzones overlying the return corner,rather than high capacity surface goaf drainage deep inthe goaf.

Simulation of Spin-3/2 Blume-Capel Model on a Cellular Automaton with Heating and Cooling Algorithm

The spin-3/2 B1ume-Capel model is studied using the heating and cooling algorithms improved from the Creutz cellular automaton （CCA）. The calculations are done on various sizes of the simple cubic lattice in the 0 ≤ D/J ≤ 5 parameter region. The phase diagram of the model and temperature variation of the thermodynamic quantities are obtained. We confirm the existence of a critical end point within the heating calculations. However, in contrast to the heating calculations, we do not obtain the first-order line at low temperature with cooling algorithm calculations. The results are compared with those of other theories.

Adaptive Thermal Comfort for Occupants of Low-Cost Dwellings in a Hot Dry Climate

Adaptive models are based on the observation that there are some actions that people can and actually do take to achieve thermal comfort. Studies regarding thermal comfort conditions in economical dwellings were carried out simultaneously in seven Mexican cities, corresponding to warm dry and warm humid climates. In this article, case studies of low-cost dwellings in the city of Hermosillo （in northwest Mexico）, are presented and analyzed. Field surveys were carried out to obtain information about the physical characteristics of the dwellings and their occupants, as well as the indoor thermal environment. Neutral temperature was obtained from the applied survey. The high neutral temperature reveals the effect of inhabitants＇ adaptation mechanism to extreme climates. Occupant comfort votes as a function of indoor air temperatures were analyzed, and different characteristics such as age, size and gender were evaluated separately. The results show the variability of the neutral temperature and the tolerance to temperature changes, depending on the population＇s specific characteristics. In many cases where the population does not have access to artificial acclimatization devices, the neutral temperature values for specific climates and people can inform architects when choosing the most suitable thermal strategies for building design.

Analysis of 13Cr bloom solidification structure using CA-FE model

Solidification structure is critical in the control of the mechanical properties and quality during the continuous casting process. The thermo-physical properties of 13 Cr steel added some rare metals, such as Mo, V, Nb, are measured to better understand the solidification structure of 13 Cr bloom. A computational model using CA-FE(cellular automation-finite element) method coupled with heat transfer model is developed to describe the solidification structure in continuous casting process. It is found that the calculated solidification structure is in good agreement with the observed data. The influence of casting speed and superheat on the solidification structure of the bloom is studied in detail. In order to obtain more equiaxed crystal ratio and low degree of the segregation in the bloom, the optimized casting speed 0.6 m/min and superheat less than 25 °C are determined for the caster. Using the optimized manufacturing parameters, these samples are 60% with the equiaxed zone ratio of 8%–10% and below the degree of segregation 1.05.

利用手持技术数字化实验探究自热包的电化学腐蚀发热原理

针对电化学腐蚀概念教学存在的不足,以手持技术数字化实验的TQVC概念认知模型为研究思路,定性与定量相结合,设计手持技术数字化实验以促进学生对电化学腐蚀概念的认知。利用温度传感器、氧化还原传感器、pH传感器,测定镁水型自热包在溶液中工作的温度曲线、氧化还原电势曲线、pH曲线,通过多重表征的手段解析镁水型自热包的腐蚀原电池工作原理、腐蚀发热原理、缓释均布剂与包埋剂的作用、各类型饭盒的加热效果,旨在帮助学生从装置-原理二维视角认识电化学腐蚀的本质,以期为日常教学提供参考。

Pricing Weather Derivatives Index based on Temperature: The Case of Bahir Dar, Ethiopia

In this paper we present a stochastic model for daily average temperature to calculate the temperature indices upon which temperature-based derivatives are written. We propose a seasonal mean and volatility model that describes the daily average temperature behavior using the mean-reverting Ornstein-Uhlenbeck process. We also use higher order continuous-time autoregressive process with lag 3 for modeling the time evolution of the temperatures after removing trend and seasonality. Our model is fitted to 11 years of data recorded, in the period 1 January 2005 to 31 December 2015, Bahir Dar, Ethiopia, obtained from Ethiopia National Meteorological Services Agency. The analytical approximation formulas are used to price heating degree days(HDD) and cooling degree days(CDD) futures. The suggested model is analytically tractable for derivation of explicit prices for CDD and HDD futures and option. The price of the CDD future is calculated, using analytical approximation formulas. Numerical examples are presented to indicate the accuracy of the method. The results show that our model performs better to predict CDD indices.

Quantum discord of thermal states of a spin chain with Calogero-Moser type interaction

In this paper,we have investigated the effect of Calogero-Moser type interaction on the quantum discord of thermal states of a spin chain.Our results imply that the quantum discord depends on the relative distance between the spins,the external magnetic field,and the temperature.By a comparison between the quantum discord and the entanglement of formation,the quantum discord is more robust than the entanglement of formation in the sense that the latter takes a zero value in a large range of the parameters,while the former takes a nonzero value.

Regular Global Attractors of Type Ⅲ Thermoelastic Extensible Beams

For β∈ R,the authors consider the evolution system in the unknown variables u and ααttu+αxxxxu+αxxtα-(β+αxu L22)αxxu=f,αttα-αxxα-αxxtα-αxxtu=0 describing the dynamics of type III thermoelastic extensible beams,where the dissipation is entirely contributed by the second equation ruling the evolution of the thermal displacement α.Under natural boundary conditions,the existence of the global attractor of optimal regularity for the related dynamical system acting on the phase space of weak energy solutions is established.

Thermal Spin Squeezing as a Signature of Thermal Global Entanglement in Heisenberg Models

We study thermal spin squeezing (TSS) and thermal global entanglement (TGE) in a general Heisenberg spin chain, in the presence of Dzyaloshinskii-Moriya interaction and an external magnetic field. We derive an inequality associating the squeezing parameter and the global concurrence, which establishes (TSS) as a signature of (TGE). The inequality reduces to equality for particular symmetric chains which also associates TSS with bipartite entanglement in such systems. We also check the results by presenting two numerical examples.

Spin-Wave Analysis of the Spin-1 Two-Dimensional Frustrated Heisenberg Antiferromagnet with the Single-Ion Anisotropy

In this paper, the lowtemperature properties of the spin1 twodimensionM frustrated Heisenberg antifer romagnet with the singleion anisotropy are investigated on a square lattice by using the spinwave theory. The influence of the frustration and anisotropy is found in the thermodynamics of the model, such as the temperature dependence of the staggered magnetization and specific heat. For some selected values of the frustration and anisotropy parameters, the results for the specific heat are compared with those of existing theories and numerical estimates. Within a spinwave analysis, we have found the evidence for an intermediate magnetically disorder phase to separate the Nel and collinear phases.

Quantum heat engine cycle working with a strongly correlated electron system

A new model of a quantum heat engine （QHE） cycle is established, in which the working substance consists of an interacting electrons system. One of our purposes is to test the validity of the second law of thermodynamics by this model, which is more general than the spin-1/2 antiferromagnetic Heisenberg model since it would recover the spin model when the on-site Coulomb interaction U is strong enough. On the basis of quantum mechanics and the first law of thermodynamics, we show no violation of the second law of thermodynamics during the cycle. We further study the performance characteristics of the cycle by investigating in detail the optimal relations of efficiency and dimensionless power output. We find that the efficiency of our engine can be expressed as η = t22/t21 in the large-U limit, which is valid even for a four sites QHE.

Thermo-hydraulic experimental validation of an integrated modular small reactor operating in full power natural circulation

Small reactors have become a new hotspot of international nuclear energy research.The nuclear heating reactor(NHR)technology developed by Tsinghua University is an important multipurpose small reactor solution with features such as high integration,modular design and full power natural circulation.A new small reactor based on the existing NHR-200 reactor was developed by the Institute of Nuclear and New Energy Technology of Tsinghua University.A full-scale natural circulation test loop with the same operating parameters as the actual reactor was built in order to experimentally validate the natural circulation ability of the reactor primary loop and heat-transfer ability of fuel assemblies and heat exchangers.Corresponding results are given in detail,including parameter validation of the reactor primary loop,flow rules of the natural circulation and heat-transfer coefficients of heaters and heat exchangers,which can be directly used in the actual reactor as a reference for optimization design.Finally,a characteristic parameter k is proposed to represent the natural circulation ability of a system.By using the new data arrangement method in the form of parameter k,comprehensive experimental results of the natural circulation can be represented by a simple integrated expression.The work in this paper is of importance in broadening application fields and pushing forward commercialization of the NHR type reactors.