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Prediction of cutting forces in machining of unidirectional glass fiber reinforced plastics composite

Surinder Kumar GILL, Meenu GUPTA, P. S. SATSANGI

《机械工程前沿(英文)》 2013年 第8卷 第2期   页码 187-200 doi: 10.1007/s11465-013-0262-x

摘要:

Machining of plastic materials has become increasingly important in any engineering industry subsequently the prediction of cutting forces. Forces quality has greater influence on components, which are coming in contact with each other. So it becomes necessary to measure and study machined forces and its behavior. In this research work, experimental investigations are conducted to determine the effects of cutting conditions and tool geometry on the cutting forces in the turning of the unidirectional glass fiber reinforced plastics (UD-GFRP) composites. In this experimental study, carbide tool (K10) having different tool nose radius and tool rake angle is used. Experiments are conducted based on the established Taguchi’s technique L18 orthogonal array on a lathe machine. It is found that the depth of cut is the cutting parameter, which has greater influence on cutting forces. The effect of the tool nose radius and tool rake angles on the cutting forces are also considerably significant. Based on statistical analysis, multiple regression model for cutting forces is derived with satisfactory coefficient (R2). This model proved to be highly preferment for predicting cutting forces.

关键词: unidirectional glass fiber reinforced plastics (UD-GFRP) composites     machining     cutting forces (tangential     feed and radial force)     ANOVA     regression modeling     carbide tool (K10)    

Catalysis and deactivation of montmorillonite K10 in the aryl O -glycosylation of glycosyl trichloroacetoimidates

Xiaoliu LI, Xinhao YAN, Zhiwei LI, Hua CHEN, Pingzhu ZHANG,

《化学科学与工程前沿(英文)》 2010年 第4卷 第3期   页码 342-347 doi: 10.1007/s11705-009-0279-1

摘要: The catalysis of montmorillonite K10 (MK10) for aryl -glycosylation of glycosyl trichloroacetimidates was investigated. It was found that the catalyst MK10 is deactivated gradually in the recycle glycosylation. The fresh and the deactivated catalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Thermogravimetric analysis (TGA), and N adsorption-desorption. The results show that the eliminated trichloroacetamide molecule deposits on the MK10, which blocks and poisons the active sites, resulting in the deactivation of the catalyst. The regeneration of the deactivated MK10 by calcination was studied preliminarily.

关键词: photoelectron spectroscopy     adsorption-desorption     glycosylation     deactivated     diffraction    

Silicon carbide waste as a source of mixture materials for cement mortar

Zhengwu Jiang, Qiang Ren, Haoxin Li, Qing Chen

《环境科学与工程前沿(英文)》 2017年 第11卷 第5期 doi: 10.1007/s11783-017-0974-y

摘要: This paper presents an investigation of the feasibility of recycling silicon carbide waste (SCW) as a source of mixture materials in the production of cement mortar. Mortars with SCW were prepared by replacing different amounts of cement with SCW, and the properties of the resulting mortars, such as the fluidity, strength and shrinkage, were studied in this work. Thermogravimetry-differential scanning calorimetry and scanning electron microscopy were employed to understand the reasons for the property changes of the mortars. The results indicate that SCW decreases the initial and 1-h fluidity of fresh mortar but improves the loss of fluidity. The mortar with SCW exhibits a lower strength at 3 d and 7 d but a higher strength at 28 d and 56 d compared to the control. The shrinkage rate of cement mortar with SCW shows an obvious decrease as the replacement ratio increases. In addition, the content of calcium hydroxide in hardened paste also shows that SCW has some impact on the hydration of the cement-SCW system. The microstructures of the hardened paste also show evidence for a later strength change of mortar containing SCW. This work provides a strategic reference for possibly applying SCW as a mixture material in the production of cement mortar.

关键词: Silicon carbide waste     Cement mortar     Fluidity     Strength     Shrinkage    

A novel method to investigate voltage stability of IEEE-14 bus wind integrated system using PSAT

K. SHARMA

《能源前沿(英文)》 2020年 第14卷 第2期   页码 410-418 doi: 10.1007/s11708-016-0440-8

摘要: The maximum demand of power utilization is increasing exponentially from base load to peak load in day to day life. This power demand may be either industrial usage or household applications. To meet this high maximum power demand by the consumer, one of the options is the integration of renewable energy resources with conventional power generation methods. In the present scenario, wind energy system is one of the methods to generate power in connection with the conventional power systems. When the load on the conventional grid system increases, various bus voltages of the system tend to decrease, causing serious voltage drop or voltage instability within the system. In view of this, identification of weak buses within the system has become necessary. This paper presents the line indices method to identify these weak buses, so that some corrective action may be taken to compensate for this drop in voltage. An attempt has been made to compensate these drops in voltages by integration of renewable energy systems. The wind energy system at one of the bus in the test system is integrated and the performance of the system is verified by calculating the power flow (PF) using the power system analysis tool box (PSAT) and line indices of the integrated test system. The PF and load flow results are used to calculate line indices for the IEEE-14 bus test system which is simulated on PSAT.

关键词: voltage stability     line indices     power system analysis tool box (PSAT)     wind system     line loading     power flow (PF)    

Effect of potassium carbonate on catalytic synthesis of calcium carbide at moderate temperature

Dejun SHI, Ke QIAO, Zifeng YAN

《化学科学与工程前沿(英文)》 2011年 第5卷 第3期   页码 372-375 doi: 10.1007/s11705-010-0570-1

摘要: Calcium carbide was successfully synthesized by carbothermal reduction of lime with coke at 1973 K for 1.5 h. The effect of potassium carbonate as additive on the composition and morphology of the product was investigated using X-ray diffraction and scanning electron microscope. Addition of potassium carbonate increased the yield of calcium carbide. The sample in the presence of potassium carbonate generated acetylene gas of 168.3 L/kg, which was 10% higher than that in the absence of potassium carbonate. This result confirmed the catalytic effect of potassium carbonate on the synthesis of calcium carbide. A possible mechanism of the above effects was that the additive, which was melted at the reduction temperature, dissolved CaO and so promoted the contact between CaO and carbon, which was essential for the solid-solid reaction to form calcium carbide.

关键词: calcium carbide     synthesis     catalysis    

Platinum on nitrogen doped graphene and tungsten carbide supports for ammonia electro-oxidation reaction

《化学科学与工程前沿(英文)》 2022年 第16卷 第6期   页码 930-938 doi: 10.1007/s11705-021-2130-2

摘要: Ammonia electrooxidation reaction involving multistep electron-proton transfer is a significant reaction for fuel cells, hydrogen production and understanding nitrogen cycle. Platinum has been established as the best electrocatalyst for ammonia oxidation in aqueous alkaline media. In this study, Pt/nitrogen-doped graphene (NDG) and Pt/tungsten monocarbide (WC)/NDG are synthesized by a wet chemistry method and their ammonia oxidation activities are compared to commercial Pt/C. Pt/NDG exhibits a specific activity of 0.472 mA∙cm–2, which is 44% higher than commercial Pt/C, thus establishing NDG as a more effective support than carbon black. Moreover, it is demonstrated that WC as a support also impacts the activity with further 30% increase in comparison to NDG. Surface modification with Ir resulted in the best electrocatalytic activity with Pt-Ir/WC/NDG having almost thrice the current density of commercial Pt/C. This work adds insights regarding the role of NDG and WC as efficient supports along with significant impact of Ir surface modification.

关键词: Ammonia electro-oxidation reaction     electrocatalyst supports     platinum     nitrogen doped graphene     tungsten carbide    

Energy saving design of the machining unit of hobbing machine tool with integrated optimization

《机械工程前沿(英文)》 2022年 第17卷 第3期 doi: 10.1007/s11465-022-0694-2

摘要: The machining unit of hobbing machine tool accounts for a large portion of the energy consumption during the operating phase. The optimization design is a practical means of energy saving and can reduce energy consumption essentially. However, this issue has rarely been discussed in depth in previous research. A comprehensive function of energy consumption of the machining unit is built to address this problem. Surrogate models are established by using effective fitting methods. An integrated optimization model for reducing tool displacement and energy consumption is developed on the basis of the energy consumption function and surrogate models, and the parameters of the motor and structure are considered simultaneously. Results show that the energy consumption and tool displacement of the machining unit are reduced, indicating that energy saving is achieved and the machining accuracy is guaranteed. The influence of optimization variables on the objectives is analyzed to inform the design.

关键词: energy saving design     energy consumption     machining unit     integrated optimization     machine tool    

PM10 emissions from industrial coal-fired chain-grate boilers

Xinghua Li, Junzan Han, Lei Duan

《环境科学与工程前沿(英文)》 2017年 第11卷 第6期 doi: 10.1007/s11783-017-0966-y

摘要: Industrial coal-fired boiler is an important air pollutant emission source in China. The chain-grate boiler is the most extensively used type of industrial coal-fired boiler. An electrical low-pressure impactor, and a Dekati Low Pressure Impactor were applied to determine mass and number size distributions of PM at the inlet and the outlet of the particulate emission control devices at six coal-fired chain-grate boilers. The mass size distribution of PM generated from coal-fired chain-grate boilers generally displays a bimodal distribution that contains a submicron mode and a coarse mode. The PM in the submicron mode for burning with raw coal contributes to 33%±10 % of PM emissions, much higher than those for pulverized boilers. And the PM in the submicron mode for burning with briquette contributes up to 86 % of PM emissions. Multiclones and scrubbers are not efficient for controlling PM emission. Their average collection efficiencies for sub-micron particle and super-micron particle are 34% and 78%, respectively. Operating conditions of industrial steam boilers have influence on PM generation. Peak of the submicron mode during normal operation period is larger than the start-up period.

关键词: coal-fired chain-grate boiler     PM10     size distribution     particulate emission control devices     size-dependent collection efficiency    

Effect of magneto rheological damper on tool vibration during hard turning

P. Sam PAUL, A. S. VARADARAJAN

《机械工程前沿(英文)》 2012年 第7卷 第4期   页码 410-416 doi: 10.1007/s11465-012-0341-4

摘要:

Recently, the concept of hard turning has gained considerable attention in metal cutting as it can apparently replace the traditional process cycle of turning, heat treating, and finish grinding for assembly of hard wear resistant steel parts. The present investigation aims at developing a magneto rheological (MR) fluid damper for suppressing tool vibration and promoting better cutting performance during hard turning. The magneto rheological Fluid acts as a viscoelastic spring with non-linear vibration characteristics that are controlled by the composition of the magneto rheological fluid, the shape of the plunger and the electric parameters of the magnetizing field. Cutting experiments were conducted to arrive at a set of electrical, compositional and shape parameters that can suppress tool vibration and promote better cutting performance during turning of AISI 4340 steel of 46 HRC with minimal fluid application using hard metal insert with sculptured rake face. It was observed that the use of MR fluid damper reduces tool vibration and improves the cutting performance effectively. Also commercialization of this idea holds promise to the metal cutting industry.

关键词: tool vibration     magneto rheological damper     hard turning     surface finish     tool wear    

Dynein axonemal heavy chain 10 deficiency causes primary ciliary dyskinesia in humans and mice

《医学前沿(英文)》   页码 957-971 doi: 10.1007/s11684-023-0988-8

摘要: Primary ciliary dyskinesia (PCD) is a congenital, motile ciliopathy with pleiotropic symptoms. Although nearly 50 causative genes have been identified, they only account for approximately 70% of definitive PCD cases. Dynein axonemal heavy chain 10 (DNAH10) encodes a subunit of the inner arm dynein heavy chain in motile cilia and sperm flagella. Based on the common axoneme structure of motile cilia and sperm flagella, DNAH10 variants are likely to cause PCD. Using exome sequencing, we identified a novel DNAH10 homozygous variant (c.589C > T, p.R197W) in a patient with PCD from a consanguineous family. The patient manifested sinusitis, bronchiectasis, situs inversus, and asthenoteratozoospermia. Immunostaining analysis showed the absence of DNAH10 and DNALI1 in the respiratory cilia, and transmission electron microscopy revealed strikingly disordered axoneme 9+2 architecture and inner dynein arm defects in the respiratory cilia and sperm flagella. Subsequently, animal models of Dnah10-knockin mice harboring missense variants and Dnah10-knockout mice recapitulated the phenotypes of PCD, including chronic respiratory infection, male infertility, and hydrocephalus. To the best of our knowledge, this study is the first to report DNAH10 deficiency related to PCD in human and mouse models, which suggests that DNAH10 recessive mutation is causative of PCD.

关键词: DNAH10     mice     motile cilia     mutation     primary ciliary dyskinesia    

Innate immune checkpoint Siglec10 in cancers: mining of comprehensive omics data and validation in patient

《医学前沿(英文)》 2022年 第16卷 第4期   页码 596-609 doi: 10.1007/s11684-021-0868-z

摘要: Sialic acid binding Ig-like lectin 10 (Siglec10) is a member of innate immune checkpoints that inhibits the activation of immune cells through the interaction with its ligand CD24 on tumor cells. Here, by analyzing public databases containing 64 517 patients of 33 cancer types, we found that the expression of Siglec10 was altered in 18 types of cancers and was associated with the clinical outcomes of 11 cancer types. In particular, Siglec10 was upregulated in patients with kidney renal clear cell carcinoma (KIRC) and was inversely associated with the prognosis of the patients. In 131 KIRC patients of our settings, Siglec10 was elevated in the tumor tissues of 83 (63.4%) patients compared with that in their counterpart normal kidney tissues. Moreover, higher level of Siglec10 was associated with advanced disease (stages III and IV) and worse prognosis. Silencing of CD24 in KIRC cells significantly increased the number of Siglec10-expressing macrophages phagocytosing KIRC cells. In addition, luciferase activity assays suggested that Siglec10 was a potential target of the transcription factors c-FOS and GATA1, which were identified by data mining. These results demonstrate that Siglec10 may have important oncogenic functions in KIRC, and represents a novel target for the development of immunotherapies.

关键词: innate immune checkpoint     Siglec10     kidney renal clear cell carcinoma    

The most influential “Top 10 Events” in carbon neutrality and climate change in 2022

《能源前沿(英文)》 2023年 第17卷 第1期   页码 1-4 doi: 10.1007/s11708-023-0869-5

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Effect of IL-10 on formation of foam cell induced by ox-LDL

WANG Fei, DAI Yalei, XU Ting, XU Bo, WANG Kaifeng

《医学前沿(英文)》 2008年 第2卷 第3期   页码 298-302 doi: 10.1007/s11684-008-0057-3

摘要: Atherosclerosis is a chronic disease that causes various cardiovascular complications. It has been realized that cellular and humoral immunity plays crucial roles in atherogenic lesion formation. In this study the effects of lipopolysaccharide (LPS) and interleukin-10 (IL-10) on the formation of foam cells during the early stages of atherosclerosis have been investigated. Macrophage was induced by phorbol myristate acetate (PMA) treatment on THP-1 cells. The cells were further stimulated by ox-LDL, ox-LDL plus LPS, ox-LDL plus IL-10 and LPS. By using an oil red O staining technique, the formation of foam cells was evaluated by lipid granules formation in the cells. The ratio of foam cell formation was increased from (9.77 ± 1.70)% to (16.27 ± 2.27)% after 24 h stimulation with ox-LDL, and the increase was observed with incubating time. The foam cells were significantly increased in the presence of LPS in a dose-dependent manner. The maximum increase of about 40% was observed. However, the significant elevation by LPS was abrogated when IL-10 was added. These results indicated that IL-10 can effectively prevent the formation of foam cells induced by ox-LDL with or without LPS. This study demonstrates that ox-LDL can cause foam cell formation from macrophages . LPS can significantly accelerate this event. IL-10, an anti-inflammatory cytokine, can inhibit the effect of ox-LDL and LPS. These results indicate that inflammatory effects in blood vessels can speed up foam cell formation. The inhibitive effect of IL-10 is an important factor for delaying atherosclerosis processes.

关键词: inflammatory     presence     interleukin-10     dose-dependent     ox-LDL    

Preface of special issue of the 10 th International Conference on CO 2 Utilization

Changjun LIU,

《化学科学与工程前沿(英文)》 2010年 第4卷 第2期   页码 109-109 doi: 10.1007/s11705-009-0258-6

Kawai型碳化钨多面砧压机的压力突破 Review

Takayuki Ishii, 刘兆东, Tomoo Katsura

《工程(英文)》 2019年 第5卷 第3期   页码 434-440 doi: 10.1016/j.eng.2019.01.013

摘要:

在众多领域中都需要扩大Kawai型碳化钨(tungsten carbide, WC)多面砧压机的压力范围,尤其是在地球科学领域。然而,40年来,在压力产生方面没有取得重大进展。

关键词: 高压     多面砧压机     碳化钨压砧     烧结的金刚石压砧     下地幔    

标题 作者 时间 类型 操作

Prediction of cutting forces in machining of unidirectional glass fiber reinforced plastics composite

Surinder Kumar GILL, Meenu GUPTA, P. S. SATSANGI

期刊论文

Catalysis and deactivation of montmorillonite K10 in the aryl O -glycosylation of glycosyl trichloroacetoimidates

Xiaoliu LI, Xinhao YAN, Zhiwei LI, Hua CHEN, Pingzhu ZHANG,

期刊论文

Silicon carbide waste as a source of mixture materials for cement mortar

Zhengwu Jiang, Qiang Ren, Haoxin Li, Qing Chen

期刊论文

A novel method to investigate voltage stability of IEEE-14 bus wind integrated system using PSAT

K. SHARMA

期刊论文

Effect of potassium carbonate on catalytic synthesis of calcium carbide at moderate temperature

Dejun SHI, Ke QIAO, Zifeng YAN

期刊论文

Platinum on nitrogen doped graphene and tungsten carbide supports for ammonia electro-oxidation reaction

期刊论文

Energy saving design of the machining unit of hobbing machine tool with integrated optimization

期刊论文

PM10 emissions from industrial coal-fired chain-grate boilers

Xinghua Li, Junzan Han, Lei Duan

期刊论文

Effect of magneto rheological damper on tool vibration during hard turning

P. Sam PAUL, A. S. VARADARAJAN

期刊论文

Dynein axonemal heavy chain 10 deficiency causes primary ciliary dyskinesia in humans and mice

期刊论文

Innate immune checkpoint Siglec10 in cancers: mining of comprehensive omics data and validation in patient

期刊论文

The most influential “Top 10 Events” in carbon neutrality and climate change in 2022

期刊论文

Effect of IL-10 on formation of foam cell induced by ox-LDL

WANG Fei, DAI Yalei, XU Ting, XU Bo, WANG Kaifeng

期刊论文

Preface of special issue of the 10 th International Conference on CO 2 Utilization

Changjun LIU,

期刊论文

Kawai型碳化钨多面砧压机的压力突破

Takayuki Ishii, 刘兆东, Tomoo Katsura

期刊论文