bluuebunny/crossref_metadata_2025 huggingface dataset:
Failure Prediction for Pressurized Thick Wall Circumferentially Welded CrMoV Steel Pipes under High Temperature
Authors: Jia Kun Rong
Published: March 2013

The failure Prediction for thick wall CrMoV steel pipes circumferentially welded was studied using the Finite Element Method (FEM) under close-ended, open-ended and axial compression conditions, respectively. The life span of failure, redistribution of stress on the welds and damage variations were obtained using damage modeling. Since there is a distinct mismatch of mechanical properties in parent material, weld material and heat affect zone, variations of damage with time, stress redistribution and failure life in each zone are different. The FEM results show that the weakness of the welds is the heat-affected zone (HAZ) where the hoop stresses increase sharply in the tertiary stage of creep. The maximum of damage of the welds lies on the inner surface of in the weld zone when failure occurs. The information is useful for assessing the performance of practical service welds in power plants pipe work.
Comparative Evaluation of Engineering Design Concepts Based on Non-Linear Substructuring Analysis
Authors: Kajtaz Mladenko , Subic Aleksandar , Takla Monir
Published: March 2013

The paper presents a novel approach to comparative evaluation of engineering design concepts that exhibit non-linear structural behaviour under load. The developed method has extended the substructures technique in order to apply the Finite Element Analysis (FEA) method to complex non-linear structural problems in the conceptual design phase. As conventional FE models based on substructures allow only linear analysis, it was necessary in this research to introduce a new algorithm capable of linearizing non-linear structural problems with sufficient accuracy in order to enable comparative evaluation of design concepts relative to each other under the given constraints and loading conditions. A comparative study with respect to model size, efficiency, accuracy and confidence was performed to validate the developed method. Obtained results indicate significant improvement over more traditional approaches to applying FEA in the conceptual design phase. The improvements achieved using the developed method compared to the traditional FE based approach are superior by a factor of 2.7 in efficiency and by a factor of 4.5 in confidence while not sacrificing the optimality of the solutions.
Crossed Helical Gears with Wheels Manufactured from Sintered Steel with Pyrohydrolysis
Authors: Miltenovic Aleksandar , Mitrovic Radivoje , Banic Milan
Published: March 2013

Crossed helical gears are used in cars and many household appliances. The trend towards increased comfort in motor vehicles has led to the utilization of more than a hundred servo-drives in luxury class automobiles. Key advantages of crossed helical gears are their simple and inexpensive design, good noise performance and high ratios that can be realized in one step. Sintered steel is a highly favorable material for wheels in crossed helical gears. They are able to satisfy high performance demands in the areas of wear, fretting, tooth fracture and pitting load capacity. This report describes the results of an examination into the use of the iron-based sintered material Fe1.5Cr0.2Mo with pyrohydrolysis in crossed helical gears, in the areas of wear resistance and other damage types under different speeds and loading conditions.
Nanoscale Material Characterization under the Influence of Aggressive Agents by Magnetic Force Microscopy and Opto-Magnetic Spectroscopy
Authors: Debeljkovic Aleksandra , Mileusnic Ivana , Djuricic Ivan , Dragicevic Aleksandra , Hut Igor , Nijemcevic Srecko
Published: March 2013

Magnetic Force Microscopy (MFM) and Opto-Magnetic Spectroscopy (OMS) were used to characterize HTCV stainless steel and aluminum. Both materials were immersed in 1.0M HCl and 1.0M CH3COOH solutions for two hours. From the OMS method it was discovered that treated materials showed differences in peak wavelengths. Topographical and magnetic features for steel plate samples showed better resistance to an aggressive medium compared to aluminum. The results and analysis of these investigations are compared and presented in this paper.
Data Acquisition and Automatisation of a Conveyor Idler Test Stand
Authors: Mitrovic Radivoje , Tasic Milan , Miskovic Zarko , Stamenic Zoran , Jovanovic Dragan
Published: March 2013

Precise determination of the time-to-failure for conveyor idlers allows the planning of regular conveyor system maintenance and well-timed replacement of worn conveyor garlands. Incidental delays in power plant coal supply leads to a significant reduction in overall thermal power plant efficiency. This paper describes a test stand for the laboratory testing of conveyor idlers, under the influence of different radial loads, which was developed by the Faculty of Mechanical Engineering at the University of Belgrade. Data acquisition and processing are also considered, which includes control, monitoring and automatisation of the test stand. Machine protective systems, which ensure a high level of machine safety, were specifically redesigned due to the importance of operator safety and health.
Improvement of Auxiliary Mechanization Operations Management at an Open-Pit Coal Mine Based on a Process Approach with ICT Support
Authors: Pantelić Snežana D. , Ivanović Gradimir , Mitrovic Radivoje , Jovanovic Dragan , Stošić Dragan , Dimitrijević Sonja
Published: March 2013

This paper presents a modern systematic approach to the improvement of the management system for auxiliary mechanization operations at an open-pit coal mine. The approach is based on an integrated model (IM) of business processes and information systems (IS). Within IS/ICT system development, implementation of GPS/GPRS technologies is also described in this paper. Experimental research on this holistic approach was performed at the thermal power plants and open-pit coal mines in Kostolac, Serbia. Results confirmed the importance of this concept for auxiliary mechanization operations management based on selected KPIs (e.g. working moto-hours of the machine) and technical parameters (e.g. readiness).
Design of Exotic Materials Machining System
Authors: Mo John , Ding Song Lin , Mackie Andrew , Brandt Milan , Sun Shou Jin , Hosseinnezhad Reza , Webb Richard
Published: March 2013

New exotic materials such as titanium alloys and carbon fiber reinforced plastics require strong hard cutters made of cubic boron nitride or polycrystalline diamond. However, the traditional mechanical diamond grinding process is slow and causes damage to the workpiece. This chapter examines the design requirements of an electrical discharge machining system that can be used to machine polycrystalline diamond tipped carbide drills. A preliminary theoretical model is described but the system complexity requires a gain scheduling approach to the control system design.
Matrine Determination in Compound Sophora Alopecuroides Suppositories by High-Performance Liquid Chromatography
Authors: Hu Hui Xiang , Zhang Xuan , Zhang Zhimin
Published: March 2013

The determination of matrine in compound sophora alopecuroides suppositories was carried out by reversed-phase high-performance liquid chromatography(RP-HPLC). Elite ODS C18(250mm×4.5mm, 5µm) column was used and acetonitrile -anhydrous ethanol-water-triethy lamine (15:22.5:62.5:0.01) was selected as the mobile phase. Meanwhile the detection wavelength 215nm was used. The linearity of matrine was in the range of 0.74-5.18µg，r=0.9991，and the average recovery was 98.52%，RSD was 1.54%. The method was proved to be simple, accurate, sensitive and reliable. It can be used for the quality control of compound sophora alopecuroides suppositories.
Study on Synthesis of 2-(1-Tert-Butoxycarbonylamino-2-Methyl-Butyl)-Thiazole-4-Carboxylic Acid Methyl Ester
Authors: Wang Xiao Ji , Zhang Jian Ting , Liu Dong Wang , Tang Lin Jun , Feng Jun Min , Chen Shi Peng
Published: March 2013

2-(1-tert-Butoxycarbonylamino-2-methyl-butyl)-thiazole-4-carboxylic acid methyl ester, the chiral unit containing thiazole of a novel cyclic depsipeptide Lyngbyabellin A which exhibited moderate cytotoxicity against KB and LoVo cells, was synthesized from N-t-Boc-L-isoleucine and L-serrine methyl ester monohydrochloride in overall yield 15% through six steps, including condensation, TBS protection, thionation, deprotection, cyclodehydration and aromatization. The ee value of the title chiral thiazole unit is up to 98％.
Study on Synthesis of 2,2-Dimethyl-3-Hydroxy-7-Octynoic Acid
Authors: Wang Xiao Ji , Zhang Jian Ting , Liu Dong Wang , Tang Lin Jun , Feng Jun Min , Chen Shi Peng
Published: March 2013

Pitipeptolide A can be disconnected across the amide bind to afford t-Boc-glycine, the linear depsipeptide and the Dhoya fragment. 2,2-dimethyl-3-hydroxy-7-octynoic acid unit was prepared in eight steps from 1,5-pentanediol monobenzyl ether. including oxidation, TBS protection, deprotection and Saponification with (1M) sodium hydroxide solution gave the Dhoya unit (8) in 75% overall yield.
Study on Synthesis of N-Methyldipeptide N-Ns-N(Me)-L-Ala-N(Me)-L-lle-OtBu
Authors: Wang Xiao Ji , Zhang Jian Ting , Liu Dong Wang , Tang Lin Jun , Li Yang
Published: March 2013

The hindered N-methyldipeptide (N-Ns-N(Me)-L-Ala-N(Me)-L-Ile-OtBu), a segment of the new cyclodepsipeptide Apratoxin A[1] , which exhibit cytotoxycity against human tumor cell lines, was synthesized from L-Alanine and L-iso-Leucine through ten steps in overall yield of 49.4%.
Utilization of Agro-Waste A. galanga Natural Fibers in Composites
Authors: Awang Mohamad , Chik Mohd Syahrizul , Rohani Mustapha , Noraaini Ali
Published: March 2013

Utilization of locally abundant agro-waste Alpinia galanga (A. galanga) natural fibers in polyethylene (PE) was investigated. The results indicate that agro-waste fibers generally function as potential natural-organic fillers as well as show an attribute of reinforcement in PE-agro-waste composites at a certain fiber loading. Minimally reduced tensile strength from 28 MPa of unfilled PE, addition of agro-waste A. galanga natural fibers also resulted in reinforcement of up to 31 MPa at 6 wt% agro-waste fibers loading. Findings also reveal that alkali treatment was effective to impart surface modification of agro-waste A. galanga natural fibers and hence improved tensile strength, modulus of elasticity and thermal stability of PE-agro-waste composites.
Synthesis of N/Al Doped TiO2 Mesoporous Nanomaterials with Pyridine as a Template
Authors: Luo Chen Yan , Liu Shao You , Feng Qing Ge
Published: March 2013

With tetrabutyl orthotitanate, hydrazine hydrate and aluminum chloride hexahydrate as original materials and pyridine as a template reagent, N/Al doped TiO2 (N-TiO2, Al-TiO2, Al-N-TiO2) mesoporous nanomaterials were successfully synthesized through a simple and environmentally friendly solid state reaction route. The textural properties of the samples were characterized by X-ray diffraction (XRD), high resolution transmission electron microscope (HRTEM), ultraviolet visible light spectroscopy (UV-Vis), X-ray photoelectron spectroscopy (XPS), Raman spectroscope and N2 adsorption-desorption at 77K. Moreover, the formation mechanism of the N/Al-doped TiO2 mesoporous material was proposed in presence of pyridine. It clearly shows that the microscopic structure of Al-N-TiO2 nanomaterial with crystal anatase phase is an irregular shape nanoparticle with size of 5~20 nm. N atoms as N3- states have been incorporated into the lattice of TiO2 or have been entered into the interstice of TiO2 lattice. Al ions occupy the sites of Ti in crystal lattices by isomorphous replacement. Either the doping of N or Al, or the co-doping of N and Al, it can effectively embarrass the crystal growth of TiO2. The specific surface area and the average pore diameter are the 138.4 m2/g and 1.9 nm, respectively. Interestingly, the UV-vis spectra display that the adsorption intensity of N-Al-TiO2 nanomaterial decreases in the order of N-Al-TiO2＞N-TiO2＞Al-TiO2.
Bioassay-Guided Isolation and Identification of a Acetylcholinesterase Inhibitors from Calophyllum polyanthum
Authors: Zhang Fei , Ren Hai Wei , Wang Yong Gang , Wang Rong , Sheng Jie
Published: March 2013

A significant acetylcholinesterase inhibitory activity was observed for the Ethanolic extract from the leaves of Calophyllum polyanthum by using TLC bioautographic method. Further bioassay-guided isolation of this extract using TLC bioautographic method resulted in obtaining a pyranochromanone, apetalic acid (1). The structure of 1 was identified by comparison of it’s spectral characteristics with previous reports. The concentration required for 50% inhibition of 1 was 0.95 mM, determined by a microplate assay. The anti-acetylcholinesterase aity of compound 1 was weak, but it was the first pyranochromanone which have anti-acetyl cholinesterase activity. As a new leading compound, it can be modified and transformed to obtain more potently active compounds.
Extraction, Purification and Characterization of Polysaccharides from Clam (Ruditapes philippinarum)
Authors: Liu Yi , Zhao Qian Cheng , Li Zhi Bo , Wang Hong Ye
Published: March 2013

Polysaccharides were extracted from clam (Ruditapes philippinarum) (RPPS) by enzymatic method, and the crude polysaccharides were purified by filtration DEAE-Sepharose Fast Flow chromatography and Sephacryl S-400 size-exclusion chromatography. Two main fractions of RPPS-1a and RPPS-1b were separated. Furthermore, characterizations, such as polysaccharides composition and thermal properties, were analyzed. The results showed that polysaccharides extraction rate was 0.89%, and polysaccharides content was 62.5%. The polysaccharides were comprised of aminosu-gars, uronic acid, fucose and sulfate, which accounted for 0.27%, 59.30%, 0.75% and 1.33%, respectively. According to the infrared spectra, both RPPS-1a and RPPS-1b were polysaccharides containing -CHO and-COOH, and RPPS-1a had an additional sulfate groups. DSC analysis revealed that RPPS-1a might have straight-chain crystals, and RPPS-1b might contain more branch-chain crystals.
Studies on the Interaction Mechanism between Lithium Chloride and Amorphous Al(OH)3
Authors: Yang Hong Jun , Li Bing , Chai Xiao Li , Li Wu
Published: March 2013

Experiments on the interaction mechanism between lithium chloride and amorphous Al(OH)3 were designed and conducted applying simulated brines and aqueous solutions, respectively. The concentrations of lithium ion in the different solutions were determined and XRD patterns of solids formed between lithium chloride and amorphous Al(OH)3 were obtained. The data were fitted according to related dynamic equations. The results show that the variation of the concentration of lithium ion with time obeys the first order reaction dynamic equation, and the mechanism of the interaction should be chemical reaction between lithium chloride and amorphous Al(OH)3. Li/Al ratio should be 1:2 in the formula of the solid products.
Optimized Ultrasonic-Assisted Extraction by Using Response Surface Methodology and Structural Analysis of Flavonoids from Alliums cepa L. var. agrogatum Don
Authors: Zhang Hai Yue , Li Peng
Published: March 2013

The response surface methodology (RSM) was used to optimize ultrasonic-assisted extraction of total flavonoids from Alliums cepa L. var. agrogatum Don (ACAD). The results indicated that the highest extraction yield of flavonoids by ultrasonic-assisted extraction could obtain to be 3.36% using ethanol concentration of 70% (v/v) as solvent and liquid to solid ratio of 17:1 (mL/g) for 48 min at the temperature of 60 °C. The total flavonoids were purified by AB-8 resin column and polyamide resin column successively. In addition, the maximum absorption wavelength of ACAD flavonoids was determined by UV spectrophotometry, followed by their structural identified and analysis for flavonoids by infrared spectroscopy, high performance liquid chromatography. It could be concluded that the flavonoids of ACAD contains quercetin.
Study on Antioxidant Activities of Pinus armandi franch Seed Oil
Authors: Guo Jian Xia , Wang Chang Lu , Wu Zhi Jian
Published: March 2013

Pinus armandi franch is a unique specialty plant in China and its seed oil contains high levels of essential fatty acids (EFA), particularly linoleic acid (LA), which has several pharmaceutical properties. Pinus armandi franch seed oil is a nice resource of linoleic acid with a content of 63% of the total fatty acids. Linoleic acid is an essential fatty acid, whose absence in a normal diet is responsible for the development of various abnormal disorders. This work reported purified LA from Pinus armandi franch seed oil could lower MDA content of lipid peroxidation on rats with hyperlipidemia significantly. TAC activity of liver, heart and serum was enhanced significantly, as well as SOD activity was increased. It demonstrated purified LA from Pinus armandi franch seed oil could improve antioxidant levels of hyperlipidemia rats effectively, enhance the activity of antioxidant enzyme and reduce the content of lipid peroxide, thereby improving lipid metabolism.
Survey and Evaluation of Heavy Metal Elements Pollution of Changchun Suburb Land
Authors: Xu Lin Lin , Zhang Li Zhong , Liu Bao Lin
Published: March 2013

It is reported that two villages and 21 samples in the suburbs of Changchun. We have made a survey and evaluate to the soil pollution of heavy metal elements(Cu, Zn, Cr, Co, Pb, Ni, As, Se, Hg, Cd) . It is show that land of Changchun suburban are not affected by pollution of heavy metal elements, and heavy metal elements includ Zn > Cr > Ni > Cu > Pb > As > Se > Cd > Hg.
Effects of Potential Enviromental Pollutant Acaricide Fenpyroximate on Juvenile Turbot (Scophthalmus Maximus)
Authors: Xu Pei Long , Na Na , Shang Lei
Published: March 2013

Juvenile turbot (Scophthalmus maximus) were exposed to acaricide fenpyroximate, and the subsequent histological, enzyme activity changes of liver tissue were examined. Histopathological examinations showed that the turbot liver is the target organ for the acaricide fenpyroximate. Analysis of liver antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX), in the exposed turbots also showed similar changes. These changes indicated that fenpyroximate caused the oxidative stress on the turbot liver, which induced the damage of antioxidant enzymes system and possible interruption of the mitochondrial redox respiratory chain. This could be one toxic mechanism of fenpyroximate to the juvenile turbot.
Application of Data Mining Technology on Analyzing a Series of Biomarkers for Diagnosis of Bone Metastasis from Different Cancers
Authors: Wang Da Lin , Ma Cheng , Wu Zheng Yu , Wang Gang , Li Ming Cheng
Published: March 2013

The aim of this study was to evaluate the value index of tumor biomarkers for diagnosis and prediction of bone metastasis by combining pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen (ICTP) in serum with other biochemical markers in patients with several cancers. All of 1253 patients and biomarkers data with cancers and the related benign diseases and 312 healthy controls were included in the study. Bioinformatics, data mining technology and statistics were carried out to calculate sum of direct positive index (SDPI) and sum of indirect positive index (SIPI). The average ICTP was higher in patients with bone metastasis from liver, gastric, lung, colorectal and pancreatic cancer, than in cancer patients without bone metastasis. For those cancers patients with bone metastasis, which could not be differentiated by single ICTP, combining with SDPI and SIPI would distinguish types of carcinama in situ from similar symptoms. The measurement of multiple tumor markers was very useful in complementary diagnosis and prediction of different carcinoma with bone metastasis bottom.
The Nitrogen Distribution Characteristics of Different Colloidal Dispersion Complex in Yitong River Sediments
Authors: Wang Ji Hong , Chen Ting Ting , Du Lian Sheng , Zhao Lan Po
Published: March 2013

The sediment of the Yitong which is located in the middle of Jilin Province is selected as the object of study. The distribution characteristics of nitrogen content in colloidal dispersion complex were studied using the improved Qiulin colloid dispersion grouping method, . The results showed that the absolute amount of nitrogen in G0>G2. Among the group of complex of < 10μm, the absolute amount of nitrogen in G2 group is maximum, but the contribution to the sediment nitrogen stability is minimal. The total weight (total G) of complex of < 10 μm accounted for about 27% of the sediment, but the content of nitrogen accounted for about 49% of the total sediment nitrogen, which indicated the importance of the complex of < 10 μm to the stabilization of the sediment nitrogen.
Sleep Electroencephalogram Analysis Based on Average Energy Dissipation
Authors: Zheng Zheng Zhong , Feng Hao , Yao Feng Hua , Jing Xiao Ru , Wang Jun
Published: March 2013

The quality of sleep has a great relationship with health. The result of sleep stage classification is an important indicator to measure the quality of sleep. It was found that the average energy dissipation about wake and the first stage of non-rapid eye movement sleep reflect on the changes of sleep stage. And it was confirmed by T test and multi-samples experiments. The average energy dissipation can apply into automatic sleep stage classification. By Multi-parameter analysis it could achieve a higher accuracy of sleep stage classification.
The MRTF Induced the Migration of Colon Cancer HT-29 Cell
Authors: Jiang Yong , Wang Hui Yan , Cai Jian Hui , Hao Feng , Guo Su Hong , Yuan Zhong Hai , Li Yan , Hou Yi Ju , Liu Lei , Zhang Lei , Li Yan
Published: March 2013

Tumor is a kind of disease with higher morbidity and mortality, which is currently a serious threat to human health, and to strengthen the prevention and treatment of neoplastic diseases has important economic and social benefits. The migration behavior of tumor cell is a key link in the process of tumor metastasis. In this study, the related cellular and molecular mechanisms of MRTF and AQP1 inducing the migration of colon cancer cells HT-29 were revealed in the respect of Gene transcription regulation. This heralded that MRTF and AQP1 could probably be a new target on treating the tumor cell migration.
Recent Advances of Application of Capillary Electrophoresis in Traditional Chinese Medicine Analysis
Authors: Xiang Qian , Gao Ying , Yang Shang Wen
Published: March 2013

The capillary electrophoresis (CE) is a powerful analytical technique in analytical chemistry and bioanalytical chemistry due to its high resolution, minimal sample requirements and low operating costs. Recent advances of application of CE for the analysis of traditional Chinese medicine is critically reviewed in this paper. After a simple discussion of the mode of separation and detection, special attention is focused on application of CE techniques and strategies for the qualitative and quantitative analysis in traditional Chinese medicine.
Alkylpyridinium Hydrosulfate Ionic Liquids as Novel Additives for Zinc Electrodeposition
Authors: Zhang Qi Bo , Hua Yi Xin , Chen Li Yuan
Published: March 2013

The effects of three novel alkylpyridinium hydrosulfate ionic liquids (ILs)-EpyHSO4, BpyHSO4 and HpyHSO4 on current efficiency (CE), energy consumption (EC), catholic polarization behavior, surface morphology and crystallographic orientation during zinc electrodeposition from acidic sulphate solution were investigated. Addition of these additives was found to increase CE, decrease EC and improve the surface morphology at lower concentrations. Voltammetric studies indicated that these additives had a pronounced inhibiting effect on Zn2+ electroreduction and polarization of the electrode was in the order: HpyHSO4 > BpyHSO4 > EpyHSO4. X-ray diffraction analysis revealed that the presence of additives did not change the structure of the electrodeposited zinc but affected the crystallographic orientation of the crystal planes.
Studies of Rice Flour Gelation in the Processing of Rice Noodles
Authors: Sun Qing Jie , Zhang Zhao Li , Xiong Liu , Dai Lei
Published: March 2013

Rice starch played an important role in the processing of rice noodles. There were significant differences in physicochemical properties such as gelatinization, swelling power, RVA paste viscosities and textural properties between rice flour and rice starch. Spectroscopic properties and crystalline properties of rice flour and rice noodles were studied by fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The results revealed that rice starch played an important role in the preparation of rice noodles. Rice protein could affect the pasting properties and textural properties of rice flour. XRD results showed during rice noodles preparation, rice starch crystal type changed from A-type to V-type. Differential scanning calorimeter (DSC) results showed that in the processing of rice noodles, the crystalline structure re-formed which indicated some amylopectin were associated orderly. We conclude that both amylose and amylopectin were associated during the processing of rice noodles.
Effects of Dimensions on the Fluid Flow and Mass Transfer Characteristics in Wavy-Walled Tubes for Steady Flow
Authors: Bian Yong Ning , Zhu Jing Bin , Li Cong Ling
Published: March 2013

Flow and mass transfer characteristics in axisymmetric sinusoidal wavy-walled tubes with different dimensions are investigated experimentally. The overall pressure drops and the mass transfer rate are measured. The results showed that the wavelength and amplitude of the wavy-walled tubes obviously affect the fluid flow and mass transfer characteristics. Especially, the mass transfer enhancement is compared with the corresponding straight-walled tube under equal pumping power condition. It is found that the greater mass transfer enhancement appears at the moderate Reynolds number, and the optimum mass transfer enhancement could be obtained in the wavy-walled tube with Fw=0.5.
A Novel Method for Producing Phenazine by Using Waste from the Synthesis Process of 4-Amino-Diphenylamine
Authors: Yang Rong Hua
Published: March 2013

Phenazine with high purity above 99.5% was recovered from waste of industrial production of 4-amino-diphenylamine by using solid-liquid separation, solvent extraction, recrystallization, sublimation and rectification. The operating condition for the recovery of phenazine was assessed and optimal operation conditions were recommended. The yield of phenazine in the waste reaches 85% or so, the rest of the waste returns to the system for further use. This novel method increased waste utilization value and reduced production cost compared with the conventional process. This research saves the cost in phenazine synthesis and reduces waste emission.
The Experimental Study on Performance of Single Screw Expander with Air as Working Fluid
Authors: Wang Jing Fu , Wang Yin Zhi , Zhang Yong , Wang Ying
Published: March 2013

A new single screw expansion machine was developed in order to improve the practical level of low temperature thermal power generation technology and the utilization of waste heat and renewable energy. With compressed air as working fluid, the power, efficiency, gas consumption rate and temperature difference of single screw expander with rotational speed variation had been studied in an established experimental apparatus of single screw expander . The results showed that, the maximum speed of expander reached 3393r/min, the maximum moment of torque reached 22N•m, the maximum power of expander was up to 4.4kW, and the maximum inlet flow rate was 32.9m3/h. The maximum temperature difference between import and export of expander reached 45°C. The lowest gas consumption rate was up to 55.2kg/kW•h, and the maximum total efficiency of expander reached 58.8%.
Cause Analysis of Plate Pitting Corrosion in Lubricating Oil Cooler of Main Equipment in Datang Weihe Thermal Power Plant
Authors: Li Zhou Ping , Hu Xiao Jian , Ma Hai Yan , Yan Si Wei , Yan Ai Jun , Feng La Jun
Published: March 2013

The plate heat exchanger in oil cooler of unit 2 in a thermal power plant became corrosion perforation after 2-year running, and severe pits were found on its surface. The material and scale composition of the lubricating oil cooler was analyzed, and it was found that the oil cooler was made of 304 stainless steel, instead of the 316 stainless steel provided by factory. The corrosion products on the corroded surface were composed of some characteristic elements in cooling water. The analysis suggested that the reason for corrosion perforation of the heat exchanger could be associated with its material composition, and the under scale corrosion formed under the action of scale deposition could also cause corrosion perforation and large-scale pits.
Effect of Austenite Transition under Pulsating Magnetism
Authors: Zheng Shen Bai , Pan Shao Hui , Wen Hui , Wang Xiaog Xiong
Published: March 2013

The austenite steel was radiated by the intermediate frequency pulsating magnetism, and the effects that pulsating magnetic on the austenite transition was studied. The result shows that the pulsating magnetism promotes the austenitic grain growth of low carbon steel. If the magnetic field intensity is increased, it could provide better performance of raw materials to cold rolling processing.
Solidification Characteristics of Al-1Fe-0.5Si-XMg Die-Casting Alloys for High Conductivity Demanding Applications
Authors: Yun Ho Seob , Park Joon Sik , Kim Jeong Min , Kim Ki Tae
Published: March 2013

Aluminum-Silicon based die-casting alloys have been extensively utilized in various industrial applications, but their relatively low electrical and thermal conductivities make them unsuitable as high conductivity parts. In this research, silicon content was restricted to a comparatively low level for higher conductivity and magnesium was added to enhance the castabilities. Al-1Fe-0.5Si-xMg alloys showed significantly higher electrical conductivity than conventional Al-Si based alloys. As the Mg content was increased, the mold filling ability measured using a fluidity serpentine test mold was a little decreased, however the hot cracking susceptibility was observed to be first increased and then decreased. The relationship between solidification characteristics and castabilities of Al-1Fe-0.5Si-xMg alloys was discussed based on the cooling curve analysis and microstructural characterization results.
First-Principles Calculations for Electrical Proterties of the Lead Anode Plate
Authors: Wang Fu Li , Chen Jing Chao , Yu Jie
Published: March 2013

Four kinds of fermi energy of lead anode plate were calculated by using first-principles. Different metals and different alloy elements of the fermi energy level were compared, the minimum electrode potential lead base alloy anode materials is known. The results calculations show that the adding alloy elements can reduce the electrode potential of the lead anode plate, four kinds of alloy systems Pb-Ag, Pb-Sb, Pb-Sr, Pb-Sn were calculated, the highest of fermi energy was Pb-Sb alloy. So the Pb-Sb alloy is expected to become the electrode potential minimum lead base alloy anode materials.
Acid Endurance and Sorption of Zn2+ of Anaerobic Granular Sludge Acclimated by Flue Gas Pretreatment Wastewater
Authors: Wang Juan , Zhong Qin
Published: March 2013

With the aim to use anaerobic granular sludge, the methanogenic activity inhibition and recovery of anaerobic granular sludge from an industrial anaerobic reactor (s1) were investigated by measuring the methane volume at low pH. A lab-scale upflow anaerobic sludge blanket (UASB) reactor was inoculated with s1.s1 was used to remove Zn2+ in wastewater. The results show that activity of s1 is similar when the pH value is 6.5 to 7.0. The methane volume is obviously decreased when the pH value is 6.0. The activity is completely inhibited when the pH value is 4.5. The activity is fully recovered when the pH is above 6.5 and hardly recovers when the pH fell to 4.5. The main Zn2+ removal mechanism is chemical adsorption.
Phase Diagram Simulation and Investigation of Microstructure of Ni-Based Alloys
Authors: Zhang Zhan Ping , Qi Yu Hong , Feng Min
Published: March 2013

To develop proper Ni-based alloys for high-temperature vitriol pump which is submitted the corrosion of vitriol and rush of liquid with solid particles, the equilibrium phase diagrams of some Ni-Cr-Fe-C-Mo-Si-Cu alloys were calculated by software Thermo-Calc. Based on the simulation results and the mechanism of sigma phase precipitation strengthening, the chemical composition of a new Ni-based alloy was proposed. The alloy was casted and treated by solid solution at 1373K+2h, followed cooling to 1323K and quenching in water at room temperature, then strengthened by ageing respectively at 973K, 1023K, 1073K, 1123K for 4h. It was investigated the phases by XRD, the microstructures by OM and SEM. The proposed alloy consists of g, s and M23C6 from 1073K to 1273K. The most amount of s phase is up to 12.45 % (mass) at 1023K, it decreases with the augment of equilibrium temperature. s phase disappears above 1323K. The amount of s phase is enough in alloy to supply good precipitation hardening at a large temperature range. Experimental results were compared with the results of phase diagram simulation by Thermo-Calc. The alloy can be effectively strengthened by sigma phase precipitation at the temperature from 1023K to 1073K. Experimental results verified the validity of phase diagram simulation.
Study of Micro-Inclusion of 20g Steel
Authors: Wang Shuo Ming , Du Cheng Liang , Gao Ju
Published: March 2013

According to the production process of 20g steel(120t BOF→ LF→ CC), some system analysis are introduced to research on the content of T[O] and [N] and the type, source, composition and quantity of micro inclusions in refining process, pouring process and casting billet. The results of the study show: the content of T[O] is 93.2ppm in the normal billet which is 37.8ppm more than that at steady state in the export of tundish. The content of T[O] is 140.5ppm in the compound casting billet which is 70.133ppm more than that at non-steady state in the export of tundish. The secondary oxidation of mould is serious at casting progress. In billet, the quality of CaS-SiO2-Al2O3 complex inclusion is the most, the quality of MnS inclusion is the second, and the quality of Al2O3 inclusion is the least. The sulphur content in micro-inclusion of billet is higher. The sulphur content in CaS-SiO2-Al2O3 complex inclusion is 3~15%, the sulphur content in MnS inclusion is 25%. The particle size of less than 10μm in micro-inclusions is the largest. The particle size of 0~5μm is about 60%, the particle size of 5~10μm is about 35%, the particle size of 10~15μm is about 5%. The average total volume rate of micro-inclusion is 0.149% in normal billet. The average total volume rate of micro-inclusion is 0.184% in compound casting billet which is 1.23 times than normal billet. The number of micro-inclusion is 36.5/ mm2 in normal billet. The number of micro-inclusion is 58.5/ mm2 in compound casting billet which is 60.27% higher than normal billet. The non-steady state casting has serious influence on billet cleanliness.
A Series of Metal Molybdates as Flame-Retardants and Smoke Suppressants for Flexible PVC
Authors: Liu Lei , Wu Wei Hong , Xue Huan Huan , Qu Hong Qiang
Published: March 2013

A series of metal molybdates were synthesized as flame-retardants and smoke suppressants for flexible poly (vinyl chloride). The powder of molybdates was characterized by the x-ray diffraction. The flame retardancy, smoke suppression and thermal behavior of PVC treated with a series of molybdates were studied by means of limiting oxygen index (LOI), smoke density rating (SDR), thermogravimetry (TG), differential thermogravimetry (DTG), differential thermal analysis (DTA) and scanning electron microscopy (SEM). The results shown that, the flame retardancy and smoke suppression performance of PVC samples depend on the strength of the Lewis acid which generated in the first degradation stage and the stability of residue char in the second stage. While the strong Lewis acid can also function as cracking catalysts in the second stage, and cracking of the principally hydrocarbon char can promote the generation of volatile organic compounds, which act as efficient fuels. This situation results in less smoke, but increased flame.
Effect of Compositions of Penetrating Agents on the Microstructure of Tungsten-Chromium Surface Composite
Authors: Jia Li Xiao
Published: March 2013

Influence of the composition of cast penetration agents on the microstructure of Tungsten-Chromium surface composite layer was researched by conventional cast penetration process with main cast penetration agents of WC and high carbon ferro-chrome. The result is shown that a certain thickness composite layer metallurgical bonding with matrix is formed on the surface of ZG230-450 cast under the condition of experiment. The relative quantity of chrome carbide and tungsten carbide in surface composite layer changes with the increase of WC and the shape of tungsten carbide changes from discontinuous reticulation into sunflower and then into banding shape with the increase of WC and high carbon ferro-chrome.
Adsorption of Pollutants from Water with Carbon Nanotubes
Authors: Li Jiang Yan , Jiang Ying Xiang
Published: March 2013

The unique morphology and structure of carbon nanotubes (CNTs) keep attracting a great number of researchers to explore the novel properties of these materials. The special structure of CNTs determines its physical and chemical properties, mainly reflected in its novel electrical, mechanical properties and excellent adsorption performance. This review summarizes the adsorption properties of CNTs and their properties related to the adsorption of various heavy metal ions, organic and inorganic pollutants from large volumes of aqueous solutions. CNTs is a kind of potential environmental material. This article also put forward future opportunities for CNTs application in environmental systems.
Flame Retardant Epoxy Resin Containing Magnesium Phosphinate
Authors: Chen Jia , Liu Ji Yan , Liu Xue Qing , Sun Shan
Published: March 2013

In this paper, magnesium methylcyclohexylphosphinate (Mg(MHP)) was used as flame retardant for epoxy resin(EP).The flame retardancy and thermal stability of Mg(MHP)/EP composites have been studied. As a result, the composite with 20-25% Mg(MHP) can achieve the satisfying flame retardancy with the limiting oxygen index (LOI) of 29.05 % and passing the UL-94 V-0 rating. TG results showed that adding Mg(MHP) into EP leads to a increase in the onset temperature of degradation and depresses the thermal decomposition below around 470 °C. Beyond 470 °C, the residue char of the composites lost more quickly compared to neat EP. A preliminary study seem to conclude that Mg(MHP) acts as the condensed source by promoting the char formation below around 470 oC and as the gas source by vaporizing at higher temperature.
Preparation of OMMT and Light-Colored and Transparent PI/OMMT Hybrid Composite Films
Authors: Lu Yun Hua , Hu Zhi Zhi , Xiao Guo Yong , Dong Yan , Chi Hai Jun
Published: March 2013

The organo-modified montmorillonite (OMMT) was prepared from Na+montmorillonite (Na+MMT) by cation exchange with cetyltrimethyl ammonium bromide (CTMAB). The light-colored and transparent polyimide (PI) and OMMT hybrid composite films from the solution of poly(amic acid)(PAA) and various amounts (0.25, 0.50, 0.75, 1.00wt%) of OMMT in N, N-dimethylacetamide (DMAc) were prepared. The PAA was synthesized from the reaction of the alicyclic dianhydrides 1,2,3,4-cyclobutanetrtracarboxylic dianhydride (CBDA) and fluorinated aromatic diamines 1,4-bis(4-amino-2-trifluoromethylphenoxy)benzene (6FAPB). The OMMT and PI/OMMT hybrid composite films were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), UV-vis transmission spectra and solubility testing. The experimental results showed that the OMMT exhibited a 2.12nm d-spacing value. These obtained PI/OMMT hybrid composites were soluble in typical imide type polar solvent. As the OMMT contents are increased, the transparency of the PI/OMMT hybrid composite films is sacrificed slightly. These PI/OMMT hybrid films are good candidates for potential solar cell flexible substrates.
Research on Explosive Compaction Technology and Properties of WC/Cu Composites
Authors: Wang Zhan Lei , Xu Hong Yu , Li Yi Fan , Mei Qun
Published: March 2013

This paper uses the explosive compaction method to produce Cu-matrix composites. The powders of Cu and WC were prepared by high-energy ball-milling. Experiments have been performed to compact powders of Cu and WC using cylindrical configuration. The results showed that the detonation velocity had effects on the density of the compacts. The effect has been detailedly studied. The compacted WC/Cu composites have been subjected to hot rolling. The microstructure, hardness, electrical conductivity and softening temperature of the composites have also been mentioned.
Progress in Catalytic Preparation of Carbon/Carbon Composites
Authors: Li Bing Ju , Li Jun , Shi Lei , Tan Zhou Jian , Liao Ji Qiao
Published: March 2013

This paper reviewed published research into catalytic fabrication techniques and recent progresses of carbon/carbon (C/C) composites. It’s described the catalytic chemical vapor deposition theory and reviewed the catalytic properties of different metal catalysts. Merits and demerits of the traditional chemical vapor deposition, improved chemical vapor deposition and other new rapid densification techniques were analyzed. The new densification techniques are to shorten the preparation cycle, but most of them are limited in the laboratory with application problems. Finally, the prospect on the application and development tendency of improved catalytic chemical vapor deposition technique is put forward in the rapid low cost fabrication of C/C composites in the future.
Development of Preparation of Boron Nitride Nanotubes
Authors: Zhang Ning , Zhou Yong Hui , Fu Ting Ting , Kan Hong Min , Wang Xiao Yang
Published: March 2013

Boron nitride nanotubes attract wide interest because of their unique structures as well as super properties. The structures, properties, synthetic methods and application studies are particularly summarized. Since they were discovered, additionally, the prospects for future research and application are proposed. In this paper, advances in researches on Boron Nitride (BN) nanotubes are reviewed, and some of technologies for preparation of BN nanotubes are described. The tip structures of BN nanotubes produced by different technologies are compared and discussed.
Droplet Size and Shape in a Flow-Focusing Microdevice
Authors: Zhang Wei , Niu Zhi Yuan , Wu Chao Qun , Xu Jin Liang
Published: March 2013

In droplet-based biochemical microreactors, the reaction rate, the content of chemicals, and the composition of final products have to be involved with the individual droplet size. The common method to determine droplet size is by the straightforward measuring of the 2D images recorded by a high speed camera from the top view, regardless of the real droplet shapes. However, this method is not always true due to the droplet deformation by the combined effects of viscous drag and channel confinements. Here we report that the real droplet could be spherical, hemispherical or flattend disk, leading to different droplet sizes even for the same 2D profiles from the top view. The new findings of this paper are crucial to avoid the improper estimation of droplet size for the droplet-based microfluidic applications.
Enhanced Microwave Absorption by Incorporating Fe3O4 Nanoparticles into Ordered Mesoporous Carbon
Authors: Zhou Hu , Zhuang Jian Dong , Liu Qian
Published: March 2013

Novel Fe3O4/ordered mesoporous carbon (OMC) composite powders have been prepared by impregnation and reduction methods for the microwave absorbing application purpose. The Fe3O4nanoparticles were encapsulated in the mesopores of OMCs, and Fe3O4contents in the composite could be easily controlled by changing the concentration of ferric nitrate solution during the preparation. The Fe3O4/OMC composites show very excellent microwave absorbing properties with respect to pure OMC samples, in a frequency ranging of 8.2-12.4 GHz. A minimum reflection loss (RL) value of -32 dB at 11.35 GHz and a broader absorption band with the RL values under -10 dB are obtained when the thickness of samples is 1.6 mm. The enhanced microwave absorption of the Fe3O4/OMC nanocomposites is contributed to the better impedance match between dielectric loss and magnetic loss, which originates from the incorporation of magnetic species into OMC.
Facile Solvothermal Method to Synthesis Eu Doped TiO2 Hollow Microspheres with Enhanced Photoluminescence
Authors: Zhuang Jian Dong , Zhou Hu , Liu Qian
Published: March 2013

Eu doped TiO2 powders have been prepared by the solvothermal process followed by calcination treatment. The furfural and dodecylamine assisted solvothermal method is a very simple way of fabricating porous TiO2 hollow spheres due to in situ hydrolysis and a self-assembled effect. By adding europium nitrate into the precursoSubscript textr solution, Eu-doped TiO2 hollow spheres with an intense photoluminescence were easily obtained. The stronger photoluminescence of Eu-doped TiO2 hollow sample can be attributed to the unique microstructures, such as uniform size distribution and the broken hollow structure, compared to solid Eu-TiO2 sample.
Rapid Synthesis of Non-Crosslinked and Monodisperse Polystyrene Microspheres
Authors: Ye Chang Ming , Yang Yan Qin , Dong Feng , Li Li , Hao Xi Long , Wang Ming Hua , Wang Xiang Yu , Zhang Hong Zhong
Published: March 2013

Non-crosslinked and monodisperse polystyrene (PS) microspheres showing uniform size were synthesized by using a dispersion polymerization technique in the presence of the Fenton reagent (FeSO4/H2O2) as an initiator. The effects of stabilizer dosage, monomer concentration, volume ratio of dispersion medium and reaction time on both the morphology and dispersity of PS microspheres were investigated. The results of transmission electron microscopy (TEM) and field emission scanning electron microscope (FESEM) indicated that the obtained PS microspheres are perfect with uniform size of about 170 nm under the optimum experimental condition. On the basis of the experimental results, the mechanism of PS polymerization was proposed, which should be helpful to guide the preparation of polymer microspheres with desired uniform size. In comparison with the conventional emulsion polymerization, this new synthesis technique with the Fenton reagent exhibits some advantages such as being a simple and fast polymerization process without deoxygenation.
Synthesis and Photocatalytic Activity of Rod-Shaped Mesoporous TiO2 Using Poly (ethylene glycol) as Templates
Authors: Shao Chang Wang , Zhou Guo Wei , Xu De Lan , Sun Bin
Published: March 2013

Rod-shaped TiO2 was synthesized via homogeneous precipitation by using PEG and urea as the structure directing agent and precipitation agent, respectively. The prepared samples were characterized by XRD, TEM, and FESEM. The XRD patterns of the samples indicated that the crystalline phase was anatase. TEM and FESEM images revealed the morphology of prepared TiO2 samples were rod-shaped, and densely packed with plenty of spherical-shaped units. RTS3 exhibited the highest photocatalytic activity for degradation of papermaking wastewater under UV light irradiation. CODCr percent degradation was about 75% under UV light irradiation in 12 h for RTS3.