瑞马唑仑复合地佐辛对烧爆伤患者术后镇痛的作用

讨论瑞马唑仑复合地佐辛在烧爆伤患者术后镇痛方面的作用。方法 纳入2021.08-2022.08时期的本院120例烧爆伤患者,随机分成对照组(采用地佐辛)和研究组(采用瑞马唑仑复合地佐辛),各60例。观察两组术后镇痛效果、精神状态、不良反应等。结果 研究组术后6、12、24、48小时疼痛程度评分、血压和心率等指标水平均低于对照组,术后12、24、48小时精神状态得分更高(P<0.05);2组干预前后不良反应发生率对比不存在差异(P>0.05)。结论 瑞马唑仑复合地佐辛用于烧爆伤患者术中镇痛中效果明显,值得临床借鉴。

300 MW机组中贮式制粉系统掺烧疆煤爆燃原因分析及对策

随着能源需求的增长,火力发电的稳定运行尤为重要,而制粉系统爆燃会威胁机组运行安全。基于此,分析电厂300 MW机组中贮式制粉系统掺烧疆煤爆燃原因,提出加强设备维护、优化操作参数、合理配煤和及时处理异常情况等对策,显著降低爆燃风险,旨在确保制粉系统的安全运行。

群体大面积烧爆复合伤患者单元化感染防控的实践及成效

目的总结群体大面积烧爆复合伤患者单元化感染防控的经验,以降低患者感染率。方法从病区环境管理和专业化感染团队的设置两方面强化单元化感染防控,控制群体大面积烧爆复合伤患者感染率。结果通过单元化感染防控,烧伤ICU物品表面及环境的细菌学培养合格率达96.0%,30 d患者零感染率、零病死率。结论遵循医院感染控制指南,制订单元化感染防控方案,对环境及物品表面进行规范化管理,可以降低群体大面积烧爆复合伤患者感染率和病死率。

爆震(烧)伤医疗处置与卫勤对策

爆震(烧)伤是一种在战时及平时均可见到的特殊类型创伤,随着新技术战争条件下爆震(烧)伤新特征,以及平时爆震(烧)伤救治新变化的出现,爆震(烧)伤越来越受到学界的重视。本文探讨本院救治的爆震(烧)伤伤员的伤情特点,总结临床救治经验,并结合救治经验提出加强爆震(烧)伤救治的卫勤对策。

工业锅炉过热器过烧爆管原因及预防

1 前言锅炉的过热器是较易出现故障的部位,而大部分故障是因为过热器过烧而引起的泄漏、爆管。工业锅炉过热器蒸汽温度一般不大于400℃,所以过热器蛇形管一般布置在锅炉炉膛出口处,属对流换热式过热器,其材料为20g钢,应用合金钢的较少,20g钢在设计壁温450℃范围之内,使用寿命在10万小时以上,但在实际运行中,因为多方面原因的影响引起过热器管壁温度超过设计值,使其预期寿命大大缩短,严重时不到一个月便使之过烧破坏,极大地影响锅炉安全经济运行。

循环流化床锅炉的爆燃及预防

针对循环流化床锅炉在运行中燃烧系统发生的爆燃情况,结合锅炉爆燃案例进行原因分析,提出了有效的预防措施。

易燃易爆场所宜使用BP机

随着通讯工具广泛使用和普及,电话机、BP机、对讲机和“大哥大”等通讯工具已被应用在各种场所。在一般场合,这些通讯工具是不会有什么危险的,但若在有爆炸混合物存在的场所内使用,就有可能引起燃烧爆炸。因为这些通讯工具在通讯呼叫时,产生高压和强电流,发生瞬间放电,出现电火花。如普通电话的电压为24伏,正常通话时电流约为30毫安。当人们拿起话筒或挂断电话的瞬间。

前馈控制理念在群体烧爆复合伤患者翻身床治疗中的应用效果

目的探讨前馈控制理念在群体烧爆复合伤患者进行翻身床治疗中的应用效果。方法采用回顾性观察性研究方法。浙江大学医学院附属第二医院于2020年6月13—14日收治15例符合入选标准的因液化天然气槽罐车爆炸所致重度烧爆复合伤患者,其中男13例、女2例,年龄33~92(66±17)岁。对所有患者从入院48 h后开始进行翻身床治疗,并导入前馈控制理念,包括组建翻身床前馈控制专项管理团队,明确医护人员在患者翻身床治疗中的职责,采取多学科医师配合策略,以“翻身床工作坊”形式对临时组建的护士团队中的80名护士进行培训并考核,制订翻身床治疗核查表、评估单并持续质控。统计患者入院30 d内翻身床翻身频率、翻身操作总次数及一次性体位变换成功率。观察治疗过程中因翻身床操作不当造成患者呼吸心搏骤停、治疗中断、非计划性拔管、坠床、皮片移位等不良事件的发生情况。记录患者入院2 d内和入院30 d动脉血氧分压(PaO2)和动脉血二氧化碳分压(PaCO_(2))最低值、氧合指数>300 mmHg(1 mmHg=0.133 kPa)患者数及急性呼吸窘迫综合征(ARDS)发生情况。结果患者入院30 d内每日行翻身床翻身2~6次,共进行翻身操作1320次,一次性体位变换成功率为99.9%(1319/1320)。翻身床治疗过程中,无一例患者发生不良事件。患者入院2 d内PaO2、PaCO_(2)最低值分别为(100±19)、(42±4)mmHg,轻、中、重度ARDS患病人数分别为10、2、3例,无一例患者氧合指数>300 mmHg。患者入院30 d时PaO2、PaCO_(2)最低值分别为(135±28)、(37±8)mmHg,中、重度ARDS患病人数分别为3、1例,有11例患者氧合指数>300 mmHg。结论在群体烧爆复合伤患者翻身床治疗中导入前馈控制理念,通过提前控制翻身床应用过程中不良事件发生的风险,确保翻身床翻身安全顺利完成,可促进烧伤创面修复和呼吸功能改善,提高患者救治质量。

Theoretical analysis of ultra-short pulsed laser ablation of SiO_2 material based on a Coulomb explosion model

Based on the kinetic theoretical Vlasov-Poisson equation, a surface Coulomb explosion model of SiO2 material induced by ultra-short pulsed laser radiation is established. The non-equilibrium free electron distribution resulting from the two mechanisms of multi-photon ionization and avalanche ionization is computed. A quantitative analysis is given to describe the Coulomb explosion induced by the self-consistent electric field, and the impact of the parameters of laser pulses on the surface ablation is also discussed. The results show that the electron relaxation time is not constant, but it is related to the microscopic state of the electrons, so the relaxation time approximation is not available on the femtosecond time scale. The ablation depths computed by the theoretical model are in good agreement with the experimental results in the range of pulse durations from 0 to 1 ps.

Investigation of Detonative Combustion Characteristics

The pressure and deflagration to detonation transition(DDT)characteristics of acetylene and oxygen flame were studied in a detonation tube.The pressure history and the flame velocity along the tube were measured with high frequency pressure transducers and ion probes.By analyzing the data recorded in the experiment,the detonation wave pressure,post wave pressure and DDT distance were obtained,together with the effects of the initial pressure varying from 2×10^(4)Pa to 10^(5)Pa,equivalence ration from 0.3 to 1.0,and mixture concentration from 60%to 100%.It was found that the detonation pressure was decreased respectively with the decrease of initial pressure,equivalence ratio and mixture concentration,but the DDT distance was enlarged.The DDT distance was found particularly sensitive to mixture concentration.

Effect of equivalence ratio on diesel direct injection spark ignition combustion

Aviation heavy-fuel spark ignition(SI)piston engines have been paid more and more attention in the area of small aviation.Aviation heavy-fuel refers to aviation kerosene or light diesel fuel,which is safer to use and store compared to gasoline fuel.And diesel fuel is more suitable for small aviation application on land.In this study,numerical simulation was performed to evaluate the possibility of switching from gasoline direct injection spark ignition(DISI)to diesel DISI combustion.Diesel was injected into the cylinder by original DI system and ignited by spark.In the simulation,computational models were calibrated by test data from a DI engine.Based on the calibrated models,furthermore,the behavior of diesel DISI combustion was investigated.The results indicate that diesel DISI combustion is slower compared to gasoline,and the knock tendency of diesel in SI combustion is higher.For a diesel/air mixture with an equivalence ratio of 0.6 to 1.4,higher combustion pressure and faster burning rate occur when the equivalence ratios are 1.2 and 1.0,but the latter has a higher possibility of knock.In summary,the SI combustion of diesel fuel with a rich mixture can achieve better combustion performance in the engine.

Numerical simulation for explosion wave propagation of combustible mixture gas

A two-dimensional multi-material code was indigenously developed to investigate the effects of duct boundary conditions and ignition positions on the propagation law of explosion wave for hydrogen and methane-based combustible mixture gas. In the code,Young's technique was employed to track the interface between the explosion products and air,and combustible function model was adopted to simulate ignition process. The code was employed to study explosion flow field inside and outside the duct and to obtain peak pressures in different boundary conditions and ignition positions. Numerical results suggest that during the propagation in a duct,for point initiation,the curvature of spherical wave front gradually decreases and evolves into plane wave. Due to the multiple reflections on the duct wall,multi-peak values appear on pressure-time curve,and peak pressure strongly relies on the duct boundary conditions and ignition position. When explosive wave reaches the exit of the duct,explosion products expand outward and forms shock wave in air. Multiple rarefaction waves also occur and propagate upstream along the duct to decrease the pressure in the duct. The results are in agreement with one-dimensional isentropic gas flow theory of the explosion products,and indicate that the ignition model and multi-material interface treatment method are feasible.

Characteristics of gas explosion flow fields in complex pipelines

The explosion flow field in five straight pipes with different diameters and one bending pipe selected from a domestic coal mine are studied by the method of numerical simulation. And the results show that,both in the straight and bending pipes, the pressure wave and velocity wave are accelerated by the rising of reaction rate. As the explosion progressed, with the temperature reaching approximately 3000 K, only one pressure wave and one reaction rate wave were observed, while several velocity waves were found.The larger diameter presented the highest relative pressure as well as the largest velocity increase and subsequent decrease inside the tube. The bent pipes caused both turbulence and kinetic energy to increase, resulting in the acceleration of the reaction rate. The burning time was 7.4% shorter than the burning time observed for the straight pipe. Based on these results, designing one explosion resistance device, and in the practical engineering applications, it was to be proved to meet the security requirements fully.

Determining Role of the Branched-Chain Reaction Mechanism in Combustion, Explosion and Detonation of Gases

The role of branching-chain mechanism in gas phase combustion is considered. The results of experimental and theoretical investigations show that contrary the accepted for a long time views, branching-chain mechanism of the reaction, competition of chain branching and termination determine the origin and features of gas phase combustion of almost all compounds not only at pressures below atmospheric dozen times, but also at atmospheric and elevated pressures, in conditions of any self-heating. The latter becomes important in the course of developing chain combustion and enhances the chain avalanche. Kinetic methods for controlling combustion, explosion and detonation of gases have been developed by taking into account the decisive role of chain avalanche in these processes. The approach is based on purposeful variation of the rates of the competing reactions of chain branching and termination by means of special small additives. Suggested methods enable not only prevent combustion and explosion, but also adjust the intensity of the process, deflagration to detonation transition and destroy stationary detonation wave at a given distance from the place of its origin.

适时放盐菜香甜

为了保持莱肴的风味、特色和营养,对烧菜何时放盐颇有讲究。一般可以分以下四种情况: 一、烧菜前先放盐:如烧香酥鸡、鸭等,应当在鸡鸭宰杀洗净后,先用适量的盐把外皮和内腔均匀地擦遍,这样蒸炸出来的鸡鸭酥烂而透味。又如烧整条鱼、炸鱼块时,先用适量的盐稍微腌渍一下。

迟到的忏悔

这是一个真实的故事。八月的一天,我相约到滁州市某信用社工作的同学家吃午饭,同学拿出一份《滁洲日报》给我看,报纸上登载我们定远县郭集乡和界牌集镇两个家庭发生液化气起火爆炸的事,同学还责怪这两家人说:“

Large-scale Experimental System for Multiphase Fuel/Air Explosions

A large-scale experimental for multiphase combustion and explosion study was developed and manufactured. The explosion tank consists of a 2 m diameter, 3.5 m long tube and ellipsoidai dames on both ends. The volume of the experimental tank is 10 ma. Pressure histories of the explosion pressure can be measured at different locations in the tank. High pressure glass windows of 200～300 mm were used to have access to the visualization of the explosion process. The explosion process of methane/air mixture and methane/coal dust/air mixture initiated by a 40 J electric spark at the center of the tank was studied in the large^scale experimental system. Five pressure sonsars were arranged in the tank with different distances from the ignition point. Ton dust dispersion traits were equipped to eject dust into the tank. A high-speed camera system was used to visualize the flame propagation during the explosion process. The characteristics of the pressure wave and flame propagated in methane/air mixtures and methane/coal dust/air mixtures have been

A Coulomb explosion theoretical model of femtosecond laser ablation materials

In this paper,a kinetic theory of Vlasov equation is proposed to depict electron and ion's nonequilibrium transport processes in a femtosecond time scale.A Coulomb explosion model of femtosecond laser ablation of materials is proposed and numerically simulated.The mechanism of surface Coulomb explosion induced by self-consisted electric field and the impact of laser parameters on the ablation of materials are quantitatively analyzed.The ablation depths calculated by the model are in good agreement with the experimental results.It is shown that,the intensity of self-consisted electric field generated on the dielectric material's surface is much greater than that generated on the metal or the semiconductor material's surface,and Coulomb explosion ablation is more easily to occur on the dielectric material's surface.

TRANSITION FROM A DEFLAGRATION TO A DETONATION IN GAS DYNAMIC COMBUSTION

The transition from a deflagration to a detonation (DDT) in gas dynamics is investigated through the process of a deflagration with a imite width flame overtaken by a shock. The problem is formulated as a free boundary value problem in an angular domain with a strong detonation and a reflected shock as boundaries. The main difficulty lies in the fact that the strength of reflected shock is zero at the vertex where the shock speed degenerates to be the same as the characteristic speed. The conclusion is that a strong detonation and a retonation (a reflected shock) form locally. Also the entropy satisfaction of this solution is presented.

Single-step chemistry model and transport coefficient model for hydrogen combustion

To satisfy the needs of large-scale hydrogen combustion and explosion simulation,a method is presented to establish single-step chemistry model and transport model for fuel-air mixture.If the reaction formula for hydrogen-air mixture is H2+0.5O2→H2O,the reaction rate model is ?? =1.13×10?5[H2][O2]exp(?46.37T0/T) mol(cm3 s)?1,and the transport coefficient model is ?=K/CP=ρD=7.0×10?5T 0.7 g(cm s)?1.By using current models and the reference model to simulate steady Zeldovich-von Neumann-Doering(ZND) wave and free-propagating laminar flame,it is found that the results are well agreeable.Additionally,deflagration-to-detonation transition in an obstructed channel was also simulated.The numerical results are also well consistent with the experimental results.These provide a reasonable proof for current method and new models.