用国产柴油机冷却水添加剂HG—KB代替俄制EXTROL的性能对比试验

通过穴蚀试验、玻璃器皿法腐蚀试验，以评价国产柴油机冷却水添加剂HG－KB和俄制EXTROL的性能，得出国产HG－KB添加剂在防穴蚀和防腐蚀性能方面均优于俄制EXTROL防蚀剂。     

高压油泵柱塞的穴蚀和预防

柴油机高压油泵柱塞副常见的损坏是磨损和穴蚀,文中分析了柱塞产生穴蚀的机理和柱塞穴蚀后对柴油机工作性能的影响,提出了防止柱塞产生穴蚀的措施。     

柴油机气缸套抗穴蚀热喷涂层的开发

研究了穴蚀条件下热喷涂层的行为特点,对不同种类涂层进行了抗穴蚀性能对比,研究了气缸套表面抗穴蚀涂层的应用技术,建立了涂层结合强度与穴蚀特征之间的相互关系.结果表明,使用不锈钢线材与复合线材效果较好,其抗穴蚀性能是无涂层气缸套的1.6倍.     

某型船用柴油机气缸盖穴蚀原因分析及改进

针对某型柴油机气缸盖穴蚀现象，分析引起气缸盖穴蚀的原因。分析表明，气缸盖冷却介质、冷却结构及使用工况等不合理均会引发穴蚀。据此提出相应的改进措施，试验验证改进措施的有效性，实船应用也取得良好的效果。     

降低油耗与减少排烟的柴油添加剂

本文从目前常见的几种国产柴油添加剂进行试验分析出发,选用了一些有机化合物作为柴油添加剂,分别测定了其节油率和烟度降低率.在此基础上配制了一种综合性能较好的组合柴油添加剂——添加剂A.结果表明,使用该添加剂,可促进柴油的完全燃烧,在一定程度上达到了节能和净化的目的.     

一种防穴蚀柱塞套结构的应用

针对PMD喷油泵配双超发动机进行可靠性试验时产生的穴蚀现象,对原有的泵体结构进行改进设计,在油道腔内增加2个挡油圈,消除了穴蚀;改进泵体结构需要较高的成本和较长的周期,因此另选方案对柱塞套进行改进设计,在柱塞套外侧增加了防护套,使从柱塞套油孔中高速流出的带有空泡的燃油直接击打在防护套上而不是泵体上,试验结果显示无穴蚀现象出现。     

柴油机气缸套穴蚀成因及防范措施

本文针对柴油机气缸套穴蚀现象,探讨穴蚀成因机理,提出了提高气缸套抗穴蚀能力的措施.有助于行业专业人士提高对穴蚀的认识,促进同行专家对穴蚀进行更深入的研究,从而尽可能的解决穴蚀对柴油机气缸套的危害.     

柴油机缸套穴蚀的初步研究

本文分析归纳了国内外有关文献中对穴蚀问题所持的各种观点和论述,吸取其合理部分;找出了其中的矛盾。结合工作实践,进行了具体分析,从空化是液体的一种物性出发,提出了穴蚀的机理,产生穴蚀的必要和充分条件;同时提出了缸套穴蚀的模型。最后运用此机理解释了缸套穴蚀中的一些现象和指出防止缸套穴蚀的途径及措施。     

热固性塑料在机体穴蚀修补技术中的应用

<正> 1 概述穴蚀现象随柴油机不断强化而日益突出起来,船用与陆用机都会产生不同程度的穴蚀损害,活塞对缸套侧推力大的一边的穴蚀更为严重。穴蚀破坏了缸套与机体的封水作用,它是影响中高速强载柴油机使用寿命和可靠性的关键问题之一。柴油机穴蚀后需作处理,缸套通常在穴蚀     

HG-440/13.7-L.YM25型循环流化床锅炉性能考核试验

介绍了HG-440/13.7-L.YM25型循环流化床锅炉的特点和性能考核试验,对循环流化床锅炉的设计和经济运行具有重要意义。     

Ketjen black carbon supported CoO@Co−N−C nanochains as an efficient electrocatalyst for oxygen evolution

We demonstrate an extremely facile in-situ pyrolysis followed by the reduction of partial Co²⁺ route to synthesize novel Ketjen black carbon (KB) supported CoO@Co?N?C (denoted as CoO@Co?NC/KB) nanochains using KB, urea and cobalt (Ⅱ) acetate as co-precursors. The as-prepared CoO@Co-NC/KB displays higher electrocatalytic activity, smaller Tafel slope and better durability for the oxygen evolution reaction than those of the benchmark commercial RuO₂ catalyst in 1.0 M KOH solution, far outperforming the control groups (i.e. CoO@Co?g-C₃N₄/KB, Co?NC/KB, CoO?NC/KB, CoO@Co/KB, CoO@Co?NC and Co₃O₄?NC/KB). The remarkable electrocatalytic performance of CoO@Co?NC/KB is primarily credited to the synergistic effect between Co and CoO species with a core-shell structure, increased active sites and considerably enhanced electronic conductivity.     

Evaluation of carbon supported Fe–Co electrocatalyst for selective oxygen reduction to use in implantable glucose fuel cell

In this research, the activity of Fe–Co/KB (ketjenblack carbon) has been studied as a cathode catalyst for oxygen reduction reaction (ORR) in phosphate buffer saline (PBS) in presence of a solution containing low concentrations of glucose and amino acids mixture (near to physiological tissue fluid in the human body). It is worthwhile to mention that Fe–Co/KB cathode catalyst with size of 3 nm, determined by TEM, indicated an exceptional selectivity towards ORR. Results also revealed that Fe–Co/KB has a higher activity compare to 80%wt Pt/C in ORR with a superior tolerance towards poisoning agents.Further electrochemical investigations were carried out in a two-chamber implantable glucose fuel cell (IGFC) utilizing Fe–Co/KB in the cathode side. Time-dependent evaluation of cell voltage at constant current discharge 0.02 mAcm⁻² in PBS (pH = 7.4) solution containing 5 mM glucose showed only 16% loss in cathode potential; demonstrating an acceptable performance of cathode catalyst in IGFC.     

Holey graphene/MnO2 nanosheets with open ion channels for high-performance solid-state asymmetric supercapacitors

Holey graphene/MnO₂ (HG/MnO₂) composites with open ion channels are synthesized by an electrostatic self-assembly method. The HG with rich in-plane nanopores is prepared via a mild etching reaction first, followed by modified with poly-diallyldimethylammoniumchloride (PDDA) to transfer the surface charge of HG nanosheets from negative to positive, which are eventually assembled on the negatively charged MnO₂ nanosheets via electrostatic attraction. As a result, the HG allows ions to pass through the graphene sheet, improving the ion transport channels. Besides, the electrostatic self-assembly between HG and MnO₂ enables the composite a high conductivity, providing effective electron transport pathways. The HG and MnO₂ sheets are observed to be tightly bounded by the transmission electron microscope (TEM), and the HG content in the composites is determined to be 9.6% to 20% by the thermogravimetric (TG) test. The HG/MnO₂-2 electrode with the HG content of around 14.8% displays the large specific capacitance of 219.3 F g⁻¹ at 0.5 A g⁻¹ and the high rate capacity of 134.7 F g⁻¹ at 10 A g⁻¹. Furthermore, the as-prepared solid-state asymmetric supercapacitors (SSAS) achieve a wide stable operating voltage of 1.8 V, a high energy density of 16.8 Wh kg⁻¹ at the power density of 224.6 W kg⁻¹, and low capacitance degradation of only 6.3% after 5000 cycles.     

Experimental investigations on the effect of fuel injection parameters on diesel engine fuelled with biodiesel blend in diesel with hydrogen enrichment

Fuel injection pressure and injection timing are two extensive injection parameters that affect engine performance, combustion, and emissions. This study aims to improve the performance, combustion, and emissions characteristics of a diesel engine by using karanja biodiesel with a flow rate of 10 L per minute (lpm) of enriched hydrogen. In addition, the research mainly focused on the use of biodiesel with hydrogen as an alternative to diesel fuel, which is in rapidly declining demand. The experiments were carried out at a constant speed of 1500 rpm on a single-cylinder, four-stroke, direct injection diesel engine. The experiments are carried out with variable fuel injection pressure of 220, 240, and 260 bar, and injection timings of 21, 23, and 25 °CA before top dead center (bTDC). Results show that karanja biodiesel with enriched hydrogen (KB20H10) increases BTE by 4% than diesel fuel at 240 bar injection pressure and 23° CA bTDC injection timing. For blend KB20H10, the emissions of UHC, CO, and smoke opacity are 33%, 16%, and 28.7% lower than for diesel. On the other hand NOx emissions, rises by 10.3%. The optimal injection parameters for blend KB20H10 were found to be 240 bar injection pressure and 23 °CA bTDC injection timing based on the significant improvement in performance, combustion, and reduction in exhaust emissions.     

Synergistic effect on hydrolytic sodium borohydride adding waste Al for hydrogen generation

Synergistic effect of sodium borohydride (NaBH₄) mixed with waste aluminum in hydrolytic system were investigated to improve the hydrogen generation (HG) efficiency. The alkaline aqueous originated from NaBH₄ hydrolysis impels the passive aluminum hydroxide film of Al surface to be dissolved, thus, mutual effect of HG amount increasing by 88% and 50% for Al powder and waste Al can, respectively. To add acid catalyst in the mutual mixture system prompts to significantly accelerate HG rate from 100 ml/min˙g to 400 ml/min˙g but raising temperature is not obviously found. It is speculated that exothermic effect dominates the NaBH₄ hydrolytic reaction and eliminates the temperature effect. In this study, the mutual hydrolyzed reaction of NaBH₄ and waste Al provides ecofriendly environment, low cost and enables to achieve higher HG rate and further uses for portable/mobile fields.     

基于80C196KB单片机的柴油机微粒过滤器控制

介绍红外再生微粒过滤器的组成、工作原理以及过滤器控制系统的设计要求和软硬件设计。采用80C196KB控制柴油机微粒过滤器再生时机和再生调节阀开度。结果表明,过滤器能及时清除累积的微粒,保持良好的工作性能,能满足车用环境的要求。     

回灌及回灌后开采对台兰河流域地下水位的影响

探讨不同的回灌及回灌后开采方式对地下水位的影响,将有助于对水资源的时空再调度并达到高效开发利用水资源。以新疆温宿县台兰河流域地下水库为例,在分析水文地质条件基础上构建了地下水流场数值模型,确定了回灌井及开采井、观测井的位置及回灌、回灌后开采方案,分析了HG1、HG2回灌井各自在全年回灌、汛期回灌时的地下水位变化情况,指出汛期回灌效果最佳;通过比较无回灌、开采无回灌、开采回灌、回灌无开采四种情况下地下水位变化情况,指出回灌后开采对区域地下水位影响显著,从而确定出HG1为最佳回灌井位。研究结果表明,摸清回灌及回灌后开采地下水的运动规律,将有利于台兰河流域地下水资源的优化调度。     

Comparative performance analysis of diesel engine fuelled with hydrogen enriched edible and non-edible biodiesel

In the present study, a comparative analysis of enrichment of hydrogen alongside diesel fuel and two different sources of biodiesel namely rice bran oil is an edible oil, and karanja oil being non-edible is tested. Hydrogen at a fixed flow rate of 7 lpm is inducted through the intake manifold. A total of six fuel samples are considered: diesel (D), hydrogen-enriched diesel (D + H₂), hydrogen-enriched 10, and 20% rice bran biodiesel blend (RB10 + H₂ and RB20 + H₂), and hydrogen-enriched 10 and 20% karanja biodiesel blend (KB10 + H₂ and KB20 + H₂). Results indicate that enrichment of hydrogen improves combustion and results in 2.5% and 1.6% increase in the brake thermal efficiency of diesel fuel and rice bran biodiesel, respectively. For karanja biodiesel the increment is negligible. Fuel consumption of the D + H? is 6.35% lower and for RB10 + H? and KB10 + H? it is decreased by 2.9% and 1.3%, respectively. The Presence of hydrogen shows the 4–38% lower CO emissions and 6–14% lower UHC emission due to better combustion. The blends RB10 + H? and KB10 + H? produce up to 6–13% higher NOx emission and that for the blends RB20 + H? and KB20 + H? it goes up to 25%. Overall rice bran oil is found to provide better performance than karanja biodiesel.     

Accurately measuring the hydrogen generation rate for hydrolysis of sodium borohydride on multiwalled carbon nanotubes/Co–B catalysts

Multiwalled carbon nanotubes supported cobalt–boron catalysts (Co–B/MWCNT) were developed via the chemical reduction of aqueous sodium borohydride with cobalt chloride for catalytic hydrolysis of alkaline NaBH₄ solution. The hydrogen generation (HG) rates were measured on an improved high-accuracy, low-cost and automatic HG rate measurement system based on the use of an electronic balance with high accuracy. The HG of Co–B/MWCNT catalyst was investigated as a function of heat treatment, solution temperature, Co–B loading and supporting materials. The catalyst was mesoporous structured and showed lower activation energy of 40.40 kJ mol⁻¹ for the hydrolysis of NaBH₄. The Co–B/MWCNT catalyst was not only highly active to achieve the average HG rate of 5.1 l min⁻¹ g⁻¹ compared to 3.1 l min⁻¹ g⁻¹ on Co–B/C catalyst under the same conditions but also reasonably stable for the continuous hydrolysis of NaBH₄ solution.     

Preparation and electrochemical characterizations of poly(3,4-dioxyethylenethiophene)/LiCoO2–Ketjenblack composite cathode in lithium-ion battery

Nano-scale carbon materials such as Ketjenblack (KB) was used to combine with traditional conductive polymer such as poly(3,4-ethylenedioxythiophene) (PEDOT) and LiCoO₂ to prepare composite cathode for lithium-ion (Li-ion) battery. The PEDOT/LiCoO₂–KB cathodes were made by electrochemical deposition of 3,4-ethylenedioxythiophene (EDOT) monomer on the pre-formed LiCoO₂–KB electrodes with 1 and 5 wt% of KB content. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were used to confirm the successful coating of PEDOT layer on the LiCoO₂ and KB components. To evaluate the effect of PEDOT coating, LiCoO₂–KB electrodes with and without PEDOT component were then tested and compared their results from different electrochemical characterizations. Homogeneity of the KB component and the presence of conductive PEDOT layer are found to be important factors in controlling the cathode properties such as the involved capacity, cycle ability, intercalation/de-intercalation rate and rate capability.