战火烧进互联网

科索沃战争是发生在20世纪末的一场高技术局部战争,在这场战争中,南联盟与以美国为首的北约除了在空地一体化战场展开角逐外,还在互联网领域打了一场看不见硝烟的战争。双方在计算机网络上通过键盘和鼠标频频“过招”,上演了一出出战争史上从未有过的好“戏”。如果说,在空地一体化战场上北约占有绝对优势的话,那么,在作为“战争处女地”的网络战领域,双方则是互有短长。

让竞争之火烧进企业本身

日立公司规定,公司所属的各家分厂都是相对独立的经营单位,在原料和零配件方面,如果公司供给分厂的产品质次价高,分厂有权拒绝接受,并可以从其它公司甚至“日立”的竞争对手那里购进。例如,半导体分厂生产的元器件如果不合要求,电视机分厂可以转向松下公司购买;反之,如果电视机分厂的示波器质量差,半导体分厂同样可以向其它公司购买。这种内部竞争是否会无形中消耗自身的力量而助长对手的发展呢?是否会使企业内部关系紧张或全面恶化呢?日立的答案是:正像外部竞争推动了整个社会生产力的发展一样,内部竞争也促进了各部门生产效率和技术水平的提高,促进了生产与需求的一致性。

让我们也“烧进去”的作品——读孙犁近作

鲁迅在谈到近代欧洲文学的时候,说过这样意思的话:看从前的作品仿佛隔岸观火,看现在的作品才自己烧进去.作为一生都在战斗不息的伟大作家,鲁迅自然是赞赏那种让人看了自己也烧进去的作品的.孙犁的作品就是让我们也烧进去的作品.这里只谈谈他近年来写的作品.这些作品,不仅没有“远离政治”,更没有远离人生.相反,它们距离政治和人生都是十分迫近的,其中所讨论到的问题,涉及政治、经济、文艺、教育、意识形态、道德伦理等等,有许多都是当代人关注的热点.试读下面的话,相信每一位热心人读了后都会怦然心动的:

维持物质燃烧的条件与灭火基本方法

火灾是失去控制的燃烧,灭火则是使用各种方法去终止燃烧进行。灭火行动也就是破坏支持燃烧进行的各种条件因素的过程。换言之,若掌握了维持燃烧进行的条件因素,则灭火就会有法可循。

A Model of Steady-State Convective Combustion of Micropore Propellants

Aim To develop a physical and mathematical model related to micropore para- meters of steady-state convective combustion of micropore propellants(MPP). Methods The micropore parameters were measured by WXT-88 mage analysis apparatus and the convective combustion characteristic of MPP was measured by a large volume closed bomb, respectively. Rasults Statistical physical model of burning in the micropore and granular burning were developed. The burning rate equation of steady-state convective combustion of MPP was obtained. Conclusions This model correlates the convective burning rate with micropores para- meters for the first time,and the calculating values of convective burning rate are in agreement with test results.The model also can be used to estimate the effects of microporous parame- ters, basic mass burning rate, MPP density and pressure in combustion chamber on the convective combustion characteristics of MPP.

Effect of CO Combustion Promoters on Combustion Air Partition in FCC under Nearly Complete Combustion

With CO combustion promoters, the role of combustion air flow rate for concerns of economics and control is important. The combustion air is conceptually divided to three parts: the air consumed by coke burning,the air consumed by CO combustion and the air unreacted. A mathematical model of a fluid catalytic cracking(FCC)unit, which includes a quantitative correlation of CO heterogeneous combustion and the amount of CO combustion promoters, is introduced to investigate the effects of promoters on the three parts of combustion air. The results show that the air consumed by coke burning is almost linear to combustion air flow rate, while the air consumed by CO combustion promoters tends to saturate as combustion air flow rate increases, indicating that higher air flow rate can only be used as a manipulated variable to control the oxygen content for an economic concern.

Effect of Gasoline Property on Formation of Intake Valve and Combustion Chamber Deposits

The cleanliness of gasoline is related to its components and properties.All commercial gasoline builds up deposits on the engine's injector,intake valve and combustion chamber,which can significantly lower the engine performance and influence exhaust gas emissions.In this study,the intake valve deposits (IVD) and combustion chamber deposits (CCD) produced from combustion of fuel containing 21 v%—42 v% of aromatics and 8 v%—31 v% of olefins have been studied using Ford engine tests,and the characteristics of deposits were studied by IR spectroscopy,TGA and elemental analysis instrument.The test results have shown that deposit formation depends on the fuel composition,especially the aromatic content in the fuel.It is also observed that there are differences in the values of IVD and CCD measured by IR spectrometry and elemental analyses.

Influence of Firing Temperature on Properties of Gun Propellants

Initial firing temperatures play an important role on the combustion rate of propellant. In gun propellants, initial temperature is a key factor for both accuracy and safety. Ideally, the initial temperature of the propellant should not influence the ballistic properties of the round. Nevertheless, constant initial temperature coefficients can not be achieved easily. This work focuses on the influence of the firing temperature on the ballistic properties, the mechanical integrity and the sensitivity to impact of nitrocellulose based propellants. Combustion rates have been determined by closed vessel tests. Ballistic properties have been investigated by firing 5.56 cartridges. The propellants have been conditioned at temperatures ranging from -54 ℃ to ＋71 ℃ before firing. The largest temperature coefficient is observed at high temperatures. The temperature sensitivity of the peak pressure in the combustion chamber can not be fully explained by the results from the closed vessel test. The authors speculated that the mechanical behaviour of the propellant grains at low temperatures influences also the overall ballistic properties of the round. Impact tests with propellants conditioned at low and high temperatures permit to investigate their mechanical strength under extreme temperatures and to better understand the propellant performance during firing. Tests on aged propellants have been conducted as well.

Turbulence Characteristics of Swirling Reacting Flow in a Combustor with Staged Air Injection

This paper presents an experimental investigation of the turbulent reacting flow in a swirl combustor with staged air injection. The air injected into the combustor is composed of the primary swirling jet and the secon-dary non-swirling jet. A three dimension-laser particle dynamic analyzer (PDA) was employed to measure the in-stantaneous gas velocity. The probability density functions (PDF) for the instantaneous gas axial and tangential ve-locities at each measuring location, as well as the radial profiles of the root mean square of fluctuating gas axial and tangential velocities and the second-order moment for the fluctuating gas axial and tangential velocities are ob-tained. The measured results delineate the turbulence properties of the swirling reacting flow under the conditions of staged combustion.

Modelling of a post-combustion CO2 capture process using extreme learning machine

This paper presents modelling of a post-combustion CO2 capture process using bootstrap aggregated extreme learning machine （ELM）. ELM randomly assigns the weights between input and hidden layers and obtains the weights between the hidden layer and output layer using regression type approach in one step. This feature allows an ELM model being developed very quickly. This paper proposes using principal component regression to obtain the weights between the hidden and output layers to address the collinearity issue among hidden neuron outputs. Due to the weights between input and hidden layers are randomly assigned, ELM models could have variations in performance. This paper proposes combining multiple ELM models to enhance model prediction accuracy and reliability. To predict the CO2 production rate and CO2 capture level, eight parameters in the process were utilized as model input variables： inlet gas flow rate, CO2 concentration in inlet flow gas, inlet gas temperature, inlet gas pressure, lean solvent flow rate, Jean solvent temperature, lean loading and reboiler duty. The bootstrap re-sampling of training data was applied for building each single ELM and then the individual ELMs are stacked, thereby enhancing the model accuracy and reliability. The bootstrap aggregated extreme learning machine can provide fast learning speed and good generalization performance, which will be used to optimize the CO2 capture process.

Combustion Synthesis of La0.8Sr0.2MnO3 and Its Effect on HMX Thermal Decomposition

Perovskite-type La0.8Sr0.2MnO3 was prepared by stearic acid gel combustion method.The obtained powders were characterized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),scaning electron micrograph(SEM)and X-ray photoelectron spectroscopy(XPS)techniques.The catalytic activity of La0.8Sr0.2MnO3 was investigated on thermal decomposition of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)by thermal gravity-differential scanning calorimetry(TG-DSC)techniques.The experimental results show that La0.8Sr0.2MnO3 is an effective catalyst for HMX thermal decomposition.The surface-adsorbed species such as H2O,OH - and adsorbed oxygen(Oad)could result in an advance in the onset temperature of HMX thermal decomposition.The mixture system of Mn 3+ and Mn 4+ ions and lattice oxygen could play key roles for the increase of the decomposition heat of HMX because these exothermic reactions could be catalyzed by La0.8Sr0.2MnO3 between CO and NOx(from the thermal decomposition of HMX)and the oxidation reaction of CO.According to the previous researches and our results,perovskite-type La0.8Sr0.2MnO3 may be used as a novel catalyst or modifier for nitrate ester plasticized polyether(NEPE)propellant.

Comment on the development and policy of the waste incineration power generation industry

Development space of the waste incineration power generation is expanding. According to the technical route of previous planning and related policies, the principles of our garbage disposal are based on sanitary landfill, supplemented by burning. However, with the accelerated process of urbanization, land resources are increasingly strained and most large cities have been unable to find a suitable landfill within the feasible urban extent, the main equipment for the incinerator and the localization of the overall process greatly reduced its capital investment and these factors will promote the rapid development of waste incineration power generation industry. Waste incineration and power generation technology has the dual benefits of environmental protection and energy and it is the development direction of waste disposal in the future. According to the condition that our country＇s waste incineration power generation started from scratch and developed rapidly in recent years ,there is a introduction about the application of the waste incineration and a brief analysis of the its obstacles in the promotion and financing, as well as the potential for future applications.

Low Steam Condition Heat Generator Combined with Advanced Oxy-Fuel Combustion LNG Gas Turbine for Power Generation

We propose a novel concept for power generation that involves the combination of a LSCHG （low-steam-condition heat generator）, such as a light water nuclear reactor or a biomass combustion boiler, with an advanced closed-cycle oxy-fuel combustion gas turbine-a type of complex and efficient oxy-fuel gas turbine. In this study, a LSCHG is designed to heat water to saturated steam of a few MPa, to assist in the generation of the main working fluids, instead of a compressor used in the advanced oxy-fuel gas turbine. This saturated steam can have a lower pressure and temperature than those of an existing nuclear power plant or biomass-fired power plant. We estimated plant performances in LHV （lower heating value） basis from a heat balance model based on a conceptual design of a plant for different gas turbine inlet pressures and temperatures of 1,300 ℃ and 1,500 ℃, taking into account the work to produce O2 and capture CO2. While the net power generating efficiencies of a reference plant are estimated to be about 52.0% and 56.0% at 1,300 ℃ and 1,500 ℃, respectively, and conventional LSCHG power plant is assumed to have an efficiency of about 35% or less for pressures of 2.5-6.5 MPa, the proposed hybrid plant achieved 42.8%-44.7% at 1,300 ℃ and 47.8%-49.2% at 1,500 ℃. In the proposed plant, even supposing that the generating efficiency of the LNG system in the proposed plant remains equal to that of the reference plant, the efficiency of LSCHG system can be estimated 37.4% for 6.5 MPa and 33.2% for 2.5 MPa, even though the LSHCG system may be regarded as consisting of fewer plant facilities than a conventional LSCHG power plant.

Effect of necrotic tissue on progressive injury in deep partial thickness burn wounds

OBJECTIVE: To evaluate the influence of necrotic tissue on progressive injury in deep partial thickness burn wounds. METHODS: Tissue specimens were cultured both for estimation of IL-8, EGF, bFGF, PDGF-AB and histopathological examination, from the pre-operation, post-operation, and non-operation wounds from seven patients with deep partial thickness burn. RESULTS: In seven specimens from the non-operation group, IL-8 release increased compared with those in the post-operation group (P

The Use of Fractal for Prediction of Burning Rate of Composite Solid Propellants

By using the fractal geometry it is possible to calculate the actual AP (Ammonium Perchlorate) surface area and oxidizer-binder interface fractal dimension in the prediction of burning rate of composite solid propellants. In this investigation, the fractal dimension was determined by a procedure known as the "Box Counting Method". Using this dimension, surface area relations were developed for the rough particles. This method was implemented in the PEM (Petite Ensemble Model) burning rate model. The comparison of burning rates for a typical propellant by the PEM and fractal model shows that the burning rates obtained by using the fractal geometry are slightly less than those obtained by the PEM model.

Combustion of nitrate ester plasticized polyether propellants

Nitrate ester plasticized polyether(NEPE)is a kind of high-energy solid propellant that has both good mechanical properties and high specific impulse.However,its unique composition makes its combustion mechanism different from both double-base propellants and composite propellants.In order to study the combustion mechanism of NEPE propellants,we improved the free radical cracking model of previous research to make it capable of predicting the burning rate of NEPE propellants.To study the combustion characteristics and provide data support for the model,an experimental system was built and four kinds of NEPE propellants with different compositions and grain size distributions were tested.The results show that our modified model can reflect the combustion characteristics of NEPE propellants with an acceptable accuracy.The difference between the model and the experimental data is mainly caused by uncertain environmental factors and the ignorance of interactions between components.Both the experimental data and the results predicted by the model show that increasing the backpressure helps to increase the burning rate of NEPE propellants.Furthermore,the grain size of the oxidizer inside the NEPE propellant has a more severe impact on the burning rate but a lighter impact on the burning rate pressure exponent in comparison with the grain size of aluminum.For aluminum-free NEPE propellants,the reaction in the gas phase is dominant in the combustion process while adding aluminum into the propellant makes the solid phase dominant in the final stage.The combustion of fine aluminum particles near the burning surface generates heat feedback to the burning surface which evidently influences the surface temperature.However,the agglomeration of coarse aluminum particles has little effect on the burning surface temperature.

An in-situ Technique for Producing Low-Cost Agricultural Biochar

Application of biochar to agricultural soils is effective to sequester atmospheric carbon and improve soil quality, but current pyrolysis and transportation costs are high, making biochar too costly to be used at the field scale. This study developed a new in-situ technique, burning and soil covering(B-SC), which can be used by farmers for production of biochar with crop residue. In this study,the air-dried feedstocks, elephant grass and corn residue, were burnt in situ for biochar production in the field. After approximately 90% of the leaves were combusted, the burning process was dramatically slowed down by covering the feedstock with soil. The biochar yield averaged 18.0 ± 1.3(n = 15) and 13.7 ± 1.3(n = 10) kg per 100 kg air-dried feedstock for the elephant grass and corn residue,respectively. The biochar properties were suitable for soil improvement. The inputs for biochar production of the B-SC process only included low labor force, open field, feedstock(e.g., grass and crop residue), and simple tools. The operation time for processing 10 kg of the corn residue by an individual farmer was 24.4 ± 4.1 min(n = 10). As compared with the conventional field burning process, the B-SC process drastically shortened the time for biomass burning and generated a significantly lower emission of smoke and thermal energy. This simple technique can be particularly practical and effective for farmers to improve the soils of poor quality in China.

Ignition Process Evolution at High Supersonic Velocities in Channel

The results of experimental research of multi-injector combustors in the regime of the attached pipe are presented.As a source of high-enthalpy working gas (air), hot shot wind tunnel IT-302M of ITAM, the Siberian Branch ofthe Russian Academy of Sciences was used. Tests have been carried out at Mach numbers 3,4 and 5, in a range ofchange of total temperature from 2000K up to 3000K and static pressure from 0.08MPa up to 0.23MPa. Injectorsection has been manufactured in two versions with a various relative height of wedge-shaped injectors with parallelfuel injection. Influence of conditions on the entrance of the combustion chamber on ignition and a stablecombustion of hydrogen was investigated. Intensive combustion of hydrogen has been received only at Machnumbers 3 and 4. Advantage of injector section with the greater relative height of injectors is revealed. Themechanism of fuel ignition in the combustion chamber of the given configuration was investigated: two-step ignitionprocess including 'kindling' and intensive combustion over all channel volume.