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Many problems like precision control difficulty, unstable structure properties, and waste of welding materials were encountered when remanufacturing hot forging die with manual arc surfacing method. Therefore, the automatic wire arc additive remanufacturing (WAAM) technology is put forward. By using failed forging die as remanufacturing substrate, this technology can bring out double advantages of cyclic utilization and high accuracy, which is of great application prospect. In this paper, the WAAM process of a failed crankshaft forging die is studied. Firstly, a new slicing algorithm which gets its outline polygon by classifying and reconstructing the intersection points of triangular patches and tangent planes is proposed. The key thought of this algorithm is to judge the order of these intersection points with normal vector and put them into the “starting” or “ending” arrays. By traversing through these two arrays, the treatment efficiency gets much better than before. Simultaneously, by parameterizing the chord length accumulation, an interpolation fitting algorithm is introduced to improve the accuracy of outline polygon and the criterion equation of outline polygon’s orientation is deduced. Then a composite filling algorithm with uniform inside and smooth margin is developed to meet the requirements of WAAM process. Finally, the WAAM process for a failed crankshaft forging die is conducted, which justifies the feasibility of the whole process.

A novel manufacturing method of hot stamping tool is proposed in this study. The four preselected materials were welded on the specimens by using tungsten inert gas arc welding. High-temperature compressive yield strength, heat conductivity, thermal expansion coefficient, and microstructures of welding materials were experimentally investigated. CuCrZr and Fe-based alloy were selected as the intermediate layer (IL) and surface layer (SL) of new hot stamping tool respectively. Moreover, the simulation results indicated that the dwell time of new tool (NT) can be saved by 25% in comparison to traditional tool (TT); the temperature of traditional and new tool would reach dynamic thermal equilibrium after 4 and 5 stamping circles respectively; the temperature and stress of new tool were always lower than traditional tool; the maximum stress of new tool in each area was always less than the yield strength of the corresponding welding materials, which demonstrated that new tool manufactured by surfacing technology could satisfy the strength requirement and deserve further research in the future.

Based on the measurement mechanism of mobility in pressure measurement while drilling, through analyzing a large number of mobility data, it is found that under the condition of water-based mud drilling, the product of mobility from pressure measurement while drilling and the viscosity of mud filtrate is infinitely close to the water phase permeability under the residual oil in relative permeability experiment. Based on this, a method converting the mobility from pressure measurement while drilling to core permeability is proposed, and the permeability based on Timur formula has been established. Application of this method in Penglai 19-9 oilfield of Bohai Sea shows: (1) Compared with the permeability calculated by the model of adjacent oilfields, the permeability calculated by this model is more consistent with the permeability calculated by core analysis. (2) Based on the new model, the correlation between the calculated mobility of well logging and the actual drilling specific productivity index bas been established. Compared with the relationship established by using the permeability model of an adjacent oilfield, the correlation of the new model is better. (3) Productivity of four directional wells was predicted, and the prediction results are in good agreement with the actual production after drilling. Key words: mobility from pressure measurement while drilling, permeability, irreducible water saturation, Timur formula, productivity prediction, Penglai 19-9 oilfield

For achieving a stable operation of coal gasification, it is crucial to understand the relationship between the microstructure and thermal conductivity of coal slags. Thermal conductivity measurements were carried out on a SiO2–Al2O3–CaO–Fe2O3–MgO slag system with a mass fraction of silica and alumina (SiO2 + Al2O3) ranging from 35 to 85 wt % using a nonstationary hot wire method. The crystallization tendency was obtained by a differential scanning calorimetry signal. Raman spectroscopy and X-ray diffraction (XRD) were combined to investigate the microstructure. The addition of (SiO2 + Al2O3) leads to a significant increase in the thermal conductivity of slags when (SiO2 + Al2O3) is higher than 55 wt %. The XRD results show that a gradual increase in the silica and alumina contents causes crystalline phase transition, resulting in an increase of bridging oxygen in the slag system. The degree of polymerization Q with variable (SiO2 + Al2O3) is quantified by Raman spectroscopy. The positive linear relations...

To improve the service life of hot forging die, the additive manufacturing algorithm and additive manufacturing device for die remanufacturing are developed. Firstly, a compound filling algorithm in which the inner zone is filled by linear scanning and the outer contour is filled by offsetting is developed in order to solve the problems encountered in filling path planning for wire arc additive manufacturing (WAAM) like staircase effect at marginal division, degenerated edge at outer contour, programming difficulty, and so forth. Meanwhile, the attitude control algorithm of welding gun is proposed to control the angle between welding gun and welding path so as to improve the welding forming quality. Secondly, the high-temperature and low-temperature wear resistances of Fe-based and Ni-based alloy are tested. The results show that Ni-based alloy has higher high-temperature wear resistance. Finally, a disabled crankshaft hot forging die is selected for application test and the results show that, using the techniques discussed in this paper, welding materials can be saved by more than 50% and machining cost can be saved by more than 60%. In addition, the surface of automatic-repaired die is smooth without oxidation, collapse, and other defects after forging 3000 times, which is much better than that of manual-repaired die.

Background Circulating DNAs or RNAs in body liquid have emerged as useful and highly potential biomarkers for noninvasive diagnostic application. Our previous study had shown that LOC553103 was an oncogenic lncRNA, however, a systematic evaluation of LOC553103 as a diagnostic and prognostic biomarker for pan-cancer has not yet been demonstrated. Method The expression data of LOC553103 were obtained from the quantitative real-time polymerase chain reaction (qRT-PCR) and The Cancer Genome Atlas (TCGA) database, respectively. The serum LOC553103 had a high diagnostic performance among the 15 types of human solid cancer. Result The relative AUC of serum LOC553103 in cancer patients ranged from 0.826 to 0.966 compared to that in healthy subjects. Furthermore, high serum level of LOC553103 was closely related to advanced tumor pathological stages. Serum level of LOC553103 declined significantly in patients after therapy. Kaplan-Meier survival analysis of TCGA data revealed that the LOC553103 was negatively correlated with survival and was a globally predictive biomarker for solid tumors. Additionally, we evaluated the oncogenic function of LOC553103 in various tumor cells, in vitro. Conclusion We concluded that circulating LOC553103 could serve as useful non-specific diagnostic biomarker for pan-cancer and prediction of treatment efficacy.

Crystallization is a significant challenge for the rheological properties of the liquid slag flowing down along the wall of entrained flow gasifier. Viscosity can increase sharply when certain crystals occur inside the slag. Chemical compositions are the intrinsic factors in determining the crystallization characteristics. In former studies, we have investigated the influence of major components such as SiO2, Al2O3, CaO, Fe2O3 as well as atmosphere based on synthetic coal slags. While for MgO, its ratio is less than the above four but higher than the other minors such as Na2O, TiO2. Therefore, in order to get a comprehensive understanding of crystallization characteristics of coal slag, the influence of MgO is investigated by four synthetic slags with different MgO ratios (0%, 4%, 8%, 12%). The experimental methods: differential scanning calorimetry (DSC), single high-temperature thermocouple system (SHTT), water quenching and calculation method -FactSage were combined to study the crystallization temperature, morphology of crystals as well as crystalline phases. The final state of slag with no MgO is almost glass with little crystals. The increase of MgO can lead to an enhancement of crystallization temperature and move the temperature–time transformation curve to high temperature region. Mg2+ ions acting as the network modifier participate actively into the crystallization process. At the temperature higher than 1200 °C, Mg2+ exists in spinel and the liquid. While as temperature decreases below 1200 °C, all the Mg2+ precipitates from the slag forming magnesium-silicate minerals such as diopside and melilite.

Crystallization inside the liquid slag can increase the viscosity, affecting flow down the wall which is associated with the temperature of critical viscosity ( T cv ). Four groups of synthetic slags with different Si/Al, Si + Al, CaO, Fe 2 O 3 ratios were sorted to study the crystallization characteristics including the crystallization tendency as well as crystallization temperature ( T crys ). Samples with base–acid ratio (R > 0.7) and Si/Al in the range of 1–4 are liable to crystallize with obvious crystallization peak on DSC curve, and the influence of R is more than that of Si/Al. The crystallization temperature ( T crys ) is found to display a linear relationship with the liquidus temperature ( T liq ). The deviation of real coal slag with synthetic slag is associated with the crystalline phases as well as the raw minerals present in the ash.

Large forming load at high temperature causes the occurrences of plastic deformation, wear, mechanical fatigue, and thermal fatigue in the large hot forging dies and resulted in their short service lives. In this study, temperature field, stress field, and wear condition of large hot forging die were predicted and evaluated by finite element modelling (FEM) analysis. Corroborated by the experimental results, analysis results demonstrated that failures mainly occurred in bridge, boss, and groove regions of the large hot forging dies. According to the analysis and experimental results, the failed large hot forging dies were refabricated by bimetal-layer weld surfacing technology with a cobalt-based superalloy (Co03) and a ferrous alloy (JXHC15). No failure was observed on these refabricated dies, after production of 25 pieces. In comparison with the conventional fabrication or prefabrication methods, this bimetal-layer weld surfacing technology reduced the fabrication cost, shortened the fabrication cycle, and elongated the service lives of large hot forging die effectively.

Ultrasonic vibration-assisted welding process was developed to improve the microstructures and mechanical properties of AZ80 Mg alloy joints. Results show that the ultrasonic vibration-assisted welding process has a significant effect on the morphology and size of both β-Mg17Al12 precipitated phases and α-Mg grains. With ultrasonic vibration treatment, the primary α-Mg grains are transformed from coarse dendrites to nearly fine equiaxed grains, and the β-Mg17Al12 phases at α-Mg boundaries are refined and become discontinuous, owing to the cavitation effects and acoustic streaming effects induced by ultrasonic vibration. The mechanical properties of AZ80 Mg alloy joints under the ultrasonic vibration-assisted process are obviously improved. And the influence mechanisms of the ultrasonic vibration-assisted welding process on joints are discussed in detail.

Bimetal-layer surfacing intensifying the working area of die by welding materials with gradient mechanical properties is an effective fabrication and refabrication technology for hot forging dies with low cost and a short cycle. Owing to the extremely high operating temperature and large stress of large hot forging dies, the selection of welding materials is quite important. In consideration of the excellent high-temperature performance of cobalt-based superalloy, a cobalt-based superalloy welding material, Co03 was designed in this study to be combined with ferrous alloys with outstanding low-temperature mechanical properties and low price to realized effective refabrication of large hot forging dies by bimetal-layer surfacing. Refabrication of dies and subsequent hot forging processes were simulated physically by bimetal-layer welding conducted on 5CrNiMo blocks and heat treatments. Compared with the combination of two ferrous alloys (JXHC30 and JXHC15), the combination of Co03 and JXHC15 exhibited more stable microstructure and mechanical properties in extreme operating conditions. To verify the feasibility of the combination of JXHC15 and Co03 in refabrication of hot forging dies through bimetal-layer surfacing, a pair of large hot forging dies were refabricated and employed in forging production. The service lives of refabricated dies were improved by dozens of times, compared with the former homogeneous 5CrNiMo dies.

Charging lithium ion battery cathode materials such as LiCoO2 to a higher voltage may simultaneously enhance the specific capacity and average operating voltage and thus improve the energy density. However, battery cycle life is compromised in high voltage cycling due to lattice instability and undesired oxidation of electrolyte. Cathode solid-electrolyte interphase (SEI), or cathode-electrolyte interphase (CEI), in situ formed at the cathode–electrolyte interface under high voltage, is critically important in understanding the cathode degradation process and crucial in improving high voltage cycle stability. Here we present in situ atomic force microscopy (AFM) investigation of CEI on LiCoO2 at high voltage. The formation of CEI is only observed at the LiCoO2 edge plane, not at the basal plane. The thin layer of Al2O3 coating completely suppresses the formation of CEI at the edge planes, and is shown to significantly improve coin cell high voltage cycle stability.

Crystallization inside the liquid slag of entrained flow gasifiers can increase the viscosity of the slag, affecting flow down the wall and resulting in operational problems. The chemical component of the slag is an intrinsic factor of crystallization characteristics. In the study presented here, Differential Scanning Calorimetry (DSC) and the Single Hot Thermocouple Technique (SHTT) were combined to investigate the influence of (SiO 2 + Al 2 O 3 ) ratios on crystallization temperature and crystalline morphology, and to construct temperature-time transformation (TTT) diagrams. Five synthetic slags with different amounts of silica and alumina (silica/alumina keeps constant) were prepared for their crystallization tendency. The mass ratio of (SiO 2 + Al 2 O 3 ) ranges from 30 to 70 wt.%. For the kinetics calculation, the Kissinger method was applied for activation energy under cooling conditions with DSC results and the JMA equation was used for crystallization mechanisms based on SHTT results under isothermal conditions. Bulk quenching samples were produced in a high temperature quenching furnace and analyzed by XRD to determine phases. The thermodynamic modeling program FactSage was also applied to predict the equilibrium composition and compared with experimental results. It turns out that crystallization of the slag with high amount of (SiO 2 + Al 2 O 3 ) was so weak that the crystals could hardly be observed. Higher basic oxides favored crystallization and led to higher crystallization temperature. When the proportion of (SiO 2 + Al 2 O 3 ) reduced to 30%, the crystallization tendency was extremely strong that the crystals formed at 1380 °C.

In entrained flow gasifiers, crystallization inside the liquid slag can cause an increase of the slag viscosity, affecting flow along the wall and resulting in operational challenges. In the study reported here, a real Chinese ash was investigated for its crystallization behavior as well as the viscosity. Differential Scanning Calorimetry (DSC) and the Single Hot Thermocouple Technique (SHTT) were combined to measure the crystallization temperature and observe the crystallization process, constructing the temperature-time transformation (TTT) diagram. The ash was heated and then quenched to determine the crystalline phases. Unlike the synthetic slag mixed with oxides, the compositions of real ash had some variations after the long time heat treatment, which may attribute to the reducing minerals in the ash. Under inert atmosphere, gehlenite and spinel were the main crystals in cooling process. While under reduced atmosphere, the amount of crystals decreased especially gehlenite. Spinel was widely distributed inside the slag with irregular shape forming a network which caused the sharp increase of viscosity. The temperature of critical viscosity ( T cv ) was around 1310 °C corresponding to the spinel proportion calculated about 20%.

Flexible electrodes with high charge storage capacity, low solid-state diffusion resistance toward charges, and excellent mechanical properties are needed for fabricating flexible energy storage devices. In this paper, an approach is described to synthesize a composite material with hollow rutile TiO(2)cuboid arrays supported on carbon fiber cloth (H-TiO2@CFC). This composite material is used as a self-supporting and binder-free anode for sodium-ion storage, delivering reversible charge capacities of 287.3 at 0.1 C and 103.3 mAh g(-1)at 50 C, respectively. The observed excellent electrochemical performance of the H-TiO2@CFC electrode is mainly attributed to its unique architecture, which facilitates ion transport, improves electron conductivity, and enables active surface reactivity toward sodium ions. In situ X-ray diffraction characterization results reveal a nearly zero strain structure of the hollow rutile TiO(2)in H-TiO2@CFC against electrochemical cycling. An analysis of the charge storage mechanism reveals a significant pseudocapacitance contribution to the charge storage, accounting for the observed high-rate performance of the electrode. A flexible full cell fabricated with the H-TiO2@CFC as the anode and Na3V2(PO4)(3)as the cathode exhibits both excellent electrochemical properties and flexibility against mechanical deformation, demonstrating the great promise of the H-TiO2@CFC composite material for flexible battery cells.

The finite element model of a die manufactured by the bimetal-gradient-layer surfacing method was established based on ZG29MnMoNi casting steel. Then, simulation was conducted to analyze the temperature field of the die and its cycle features under working conditions. By comparing the microstructure and properties of cast-steel matrix of the die before and after producing 5761 parts on a 63MN hot die forging press, sensitive indexes that affect the service life of the surfacing die were determined. The results have shown that the microstructure of cast-steel matrix before and after service is both pearlites and ferrites. When it is closer to the welding line, the carbides precipitate out more obviously, the dendrites segregate less, and the microstructure tends to be more compact. The mechanical properties are decreased as a whole after service: the tensile strength, yield strength, reduction of area, and elongation are declined by 7, 17, 24, and 18 %, respectively. Meanwhile, microhardness and impact toughness have shown a decrease of 10 and 28.6 %, respectively. The working temperature has a strong relationship with microstructure and property changes. The performance of cast-steel matrix after service can still satisfy the operating requirements of the 63MN hot die forging press, which can be recycled in remanufacturing process.

In entrained flow gasifiers, crystallization inside the liquid slag can increase the viscosity of the slag, affecting flow down the wall and resulting in operational challenges. Chemical composition of the slag is an intrinsic factor of crystallization characteristics. In the study reported here, five synthetic slags with different SiO 2 /Al 2 O 3 (S/A) ratios from 0.5 to 4.5 were investigated for their crystallization tendency. Differential Scanning Calorimetry (DSC) and the Single Hot Thermocouple Technique (SHTT) were combined to measure the influence of S/A on crystallization temperature and crystalline morphology, and to construct Temperature Time Transformation (TTT) diagrams, which can be an practical operation guide of temperature to a gasifier. For the kinetics calculation, the Kissinger method was used for activation energy based on DSC results under cooling conditions and the JMA equation was applied for crystallization mechanisms under isothermal conditions with SHTT results. Understanding the crystallization temperature is significant to the practically operation of gasifier when using a crystalline slag. It turns out that crystallization of the slag with low S/A (0.5) was so weak that the crystals could hardly be observed while the S/A range from 2.5 to 3.5 favored crystallization around 1100–1250 °C. As the S/A increased to 4.5, crystallization was retarded and shifted to a lower temperature range, below 1150 °C. Bulk quenching samples were produced in a high temperature quenching furnace and analyzed by XRD to determine phases. The thermodynamic modeling program Factsage was also applied to predict solids in equilibrium and compared with experimental results.

Sulfurized carbon is a promising candidate for cathode materials in practical lithium–sulfur batteries due to its high and stable capacity retention, extremely low self-discharge, and excellent safety. The main disadvantage is the relatively low sulfur content in sulfurized carbon materials. Borrowing the idea from rubber crosslinking chemistry, here we report the use of a vulcanization accelerator in carbon sulfurization. Vulcanization accelerators significantly improve sulfur content by ∼8 wt%, which results in a remarkable increase in the discharge capacity of corresponding Li–S batteries by ∼120 mA h g−1 while maintaining the outstanding cycling stability and low self-discharge. The effectiveness of this approach and the wide variety of vulcanization accelerator chemistry will pave the way for sulfurized carbon materials towards practical applications in Li–S batteries.

Crystallization in the molten slag of entrained-flow coal gasifiers can increase its viscosity and affect the flow of the slag layer along the wall. The chemical composition of the slag plays an important role in crystallization behavior and crystal characteristics. The aim of the work reported here is to study the influence of Fe2O3 on crystallization tendency. Six synthetic slags with different Fe2O3 concentrations, ranging from 5 to 30 wt %, were investigated using differential scanning calorimetry (DSC) and the single hot thermocouple technique (SHTT). In addition, three of the slags were reduced in a 60:40 CO/CO2 atmosphere, and their crystallization characteristics were compared to the original slags. The time–temperature–transformation (TTT) diagrams for each slag were constructed. The Kissinger method was used to calculate the activation energy based on DSC results under cooling conditions, and the Johnson–Mehl–Avrami (JMA) equation was applied to calculate crystallization mechanisms under isother...

In slagging gasifiers, the crystallization ratio and crystal morphology are of great importance to fluidity of slag. Although increasing attention has been paid to the influence of crystallization on viscosity, few studies have investigated crystallization kinetics in slag melts due to challenges associated with high temperature and experimental complexity. In order to gain an understanding of crystallization characteristics, an in-situ observation Single Hot Thermocouple Technique (SHTT) system was set up and direct observation of the crystallization process was conducted. After completely melting, the slag would form a film as a result of its surface tension on the tip of the thermocouple. When the slag reached a certain degree of undercooling, crystals would precipitate from the homogenous melt. The crystallization ratio was quantitatively determined by taking advantage of the crystal color difference from the surroundings. A synthetic slag was produced from five oxides, with composition 38.4SiO2–14.8Al2O3–20.8CaO–19.1Fe2O3–6.9MgO, which is modeled on a real Chinese coal ash slag with low liquidus temperature and distinct crystallization characteristics. The crystallization characteristics of this synthetic slag were studied under isothermal temperatures and continuous cooling rates. Temperature Time Transformation (TTT) and Continuous Cooling Transformation (CCT) diagrams of the slag were constructed and a fundamental understanding of crystallization influenced by temperature and cooling rates was obtained. With decreasing temperature or increasing cooling rates, the crystals became finer and smaller. At lower temperatures with high degrees of undercooling the incubation time was shortened and the crystallization ratio increased. The influence of cooling rate was not significant until it exceeded 80 °C/min. Then the growth of crystals was greatly suppressed by high cooling rates, even appearing glassy when it surpassed the critical cooling rate. Based on the classic JMA equation, the crystallization kinetics and mechanism were determined. The Avrami parameter n indicates that at temperatures higher than 1200 °C, interfacial reaction mainly controlled the crystallization process, while at lower temperatures, diffusion was dominant. The crystals formed in different temperature regions may be different phases, which can also be predicted by Factsage Software, but needs further validation.

A significant challenge for operation of entrained-flow coal gasifiers is the crystallization that occurs inside the liquid slag, which results in an increase in viscosity and slower flow of the slag along the wall. The chemical composition of slag is an intrinsic factor in determining crystallization characteristics. In this study, nine synthetic slags with various CaO concentrations (5–45%) were investigated for their crystallization tendency. Differential scanning calorimetry (DSC) and observations using the single hot thermocouple technique (SHTT) were combined to measure the influence of CaO on the crystallization temperature and crystalline morphology and to construct temperature–time transformation (TTT) diagrams. The crystalline phases were determined using scanning electron microscopy (SEM) with an energy-dispersive X-ray detector (EDX) and were compared to phases predicted by FactSage simulations. For the prepared slags, the wide range of CaO concentrations considered crossed through several sta...

There are many drawbacks of traditional mold manufacturing technology, especially for dies used on large-scale hydraulic press, such as poor forging penetration, high difficulty of open die-forging process of modules, inferior hardness after heat treatment, high cost, massive waste of invalid forging dies, and so on. Therefore, a new method of mold making is put forward in this paper, which is to do surface welding on casting-steel. The FEM simulation experiments were done to establish a simplified finite element model of the surface welding mold based on JXZG casting-steel. Then, the thermal cycle curve method was used to simulate the surface welding and tempering process. Meanwhile, the temperature field and residual stress field under different welding thickness were analyzed. The finite element modal of landing gear used in a large civil aircraft was established, and then elastic-plastic finite element method was utilized to simulate the forming process of billet and to analyze the temperature field and residual stress distribution of different time. The results demonstrated that FEM could simulate the actual process of surface welding on casting-steel effectively. The equivalent stress close to welding line decreased when the welding thickness inclined, and then it leveled out when the welding thickness was 15 mm; on contrary, the equivalent stress far from welding line increased when the welding thickness declined and the impact of weld pass on casting-steel matrix enlarged which increased the possibility of defects when the casting-steel was used. In sum, when the impact of welding thickness and the cost of mold making are taken into consideration, 16 mm was chosen as the optimal surface welding thickness under given working conditions of landing gear.

In this paper, the effects of Zn foil on the wetting ability, microstructure and mechanical properties of Mg-steel joints were investigated. TIG welding-brazing technology was performed to achieve the joining of Mg alloy and steel. The main results are shown as follows. With the applying of Zn foil, the wetting property of molten metal on solid steel plate was improved and the contact angle of Mg-steel joint decreased at the same time. The width of weld seam increased under the influence of Zn interlayer. A 2 μm thick Fe–Al reaction layer formed at the interfacial area of joint gained by directly welding of Mg-steel. However, an Mg–Zn reaction layer with the thickness of 10 μm occurred with the applying of Zn interlayer, which is the key to achieve reliable joining of Mg-steel. And the thickness of Mg–Zn layer increased with the increase of current. For the traditional TIG welded Mg-steel joint, the maximum tensile shear load is only 158 N mm−1. With the applying of Zn foil, the maximum tensile shear load of Mg-steel joint increased to 211 N mm−1 and fracture location was at the fusion area.

A double-layer (DL) film with a TiO2 nanosheet-layer on a layer of TiO2 nanorod-array, was synthesized on a transparent conductive fluorine-doped tin oxide substrate by a two-step hydrothermal method. Starting from the precursors of NaSeSO3, CdSO4 and the complex of N(CH2COOK)3, CdSe quantum dots (QDs) were grown on the DL-TiO2 substrate by chemical bath deposition method. The samples were characterized by X-ray diffraction, Scanning electron microscopy, Energy dispersion spectroscopy, and their optical scattering property was measured by light reflection spectrometry. Some CdSe QDs sensitized DL-TiO2 films serve as the photoanodes, were assembled into solar cell devices and their photovoltaic performance were also characterized. The short circuit current and open-circuit voltage of the solar cells range from 0.75 to 4.05 mA/cm2 and 0.20 − 0.42 V under the illumination of one sun (AM1.5, 100 mW/cm2), respectively. The photocurrent density of the DL-TiO2 film is five times higher than that of a bare TiO2 nanorod array photoelectrode cell.

To solve problems encountered in manufacturing forging die used on large-scale hydraulic press with traditional method, such as poor forging penetration, long cycle, high cost, etc, a new method of mold making was put forward, which adopted casting steel as substrate and used two surfacing layers– the bimetal-gradient-layer(BGL)– on the working area of die cavity to make forging die. Firstly, the processes and materials were chosen according to the operating requirements of equipment and BGL surfacing samples were prepared. Then, properties analyses of samples were conducted. The application experiment was done on 50MN hydraulic press. The results showed that this method could shorten the manufacturing cycle and reduce cost apparently; properties between substrate and surfacing layers transited smoothly; the properties of die manufactured by BGL surfacing method could meet the requirements of 50 MN hydraulic press well, which justified the new method's effectiveness.

The effects of alloying elements on the macrostructures, microstructures and tensile strength of AZ80 Mg alloy weldments were studied in the present study. The results indicate that with the decrease of Al element content of filler wire, the welding defects of seam are gradually eliminated and the β-Mg17Al12 phases at α-Mg boundaries are refined and become discontinuous, which are beneficial to the improvement of tensile strength. With AZ31 Mg alloy filler wire, the maximum tensile strength of AZ80 weldment is 220 MPa and fracture occurs at the welding seam of joint. It is experimentally proved that robust AZ80 Mg alloy joints can be obtained by tungsten inert gas (TIG) welding process with AZ31 Mg alloy filler wire. However, further study is required to improve the microstructures and reduce welding defects of joint in order to further improve the joining strength of AZ80 Mg alloy joint.

The clinical efficacy and safety of acupuncture in the treatment of Seasonal Allergic Rhinitis (SAR) was evaluated by employing a two-phase crossover single-blind clinical trial. Thirty subjects were randomly assigned to two groups with 17 and 13 subjects respectively and treated with real or sham acupuncture (three times per week) for four consecutive weeks and then a crossover for treatments for a further four weeks without a washout period. The administration of real acupuncture treatment was guided by a syndrome differentiation according to Chinese Medicine Theory. Subjects were assessed by various criteria before, during and after the treatments. Outcome measures included subjective symptom scores using a five-point scale (FPS), relief medication scores (RMS) and adverse effect records. Twenty-six (26) subjects completed the study. There was a significant improvement in FPS (nasal and non-nasal symptoms) between the two types of acupuncture treatments. No significant differences were shown in RMS between the real acupuncture treatment group and the sham acupuncture treatment group. No side effects were observed for both groups. The results indicate that acupuncture is an effective and safe alternative treatment for the management of SAR.

A bolometer imaging system mounted on different toroidal and poloidal locations used for radiation observation has been developed in the Joint Texas Experimental Tokamak (J-TEXT tokamak). Three miniature pinhole AXUV16ELG (16 elements absolute extreme ultraviolet silicon photodiodes) array cameras, which are settled down in the same toroidal position but in three different poloidal places, can provide a broad viewing angle that covers the whole plasma cross-section, and hence can measure the total radiated power and provide the radiated emissive profile, while nine AXUV10EL (10 elements absolute extreme ultraviolet silicon photodiodes) array cameras are divided into three groups and will be mounted on different toroidal locations to observe the toroidal radiated power distribution. Among these detectors, one element of the AXUV16ELG array is absolutely calibrated by the synchrotron radiation source to verify the system reliability. Although there are some discrepancies between the typical responsivity given by IRD Co. and the calibrated results, it is confirmed that the discrepancies have no major effect on the final result after the simulation. The details of the system as well as observations are presented in the paper.

MSR (moisture separator reheater) has an important effect on the safe and economic operation of the steam turbine unit in the nuclear power plant. The thermodynamic calculation is the basic of design and operation of MSR. In this study, a new method of thermodynamic calculation of MSR is proposed. The calculated results indicated that the method can be used for the primary design and the check of heating surface area in MSR. Furthermore, the results verify previous research on the condensation in horizontal tube.

A dc method, which needs no complex numerical calculation and expensive hardware configuration, was developed to measure the cross-plane thermal conductivity of thin films in this paper. Two parallel metallic heaters, which were deposited on different parts of the sample, serve simultaneously as the heaters and temperature sensors during the measurement. A direct current was flowed through the same two metallic strips to heat the thin-film sample. The heating power and the heater's temperature were obtained by a data acquisition device, and the thermal conductivity of thin film was calculated. To verify the validity of the dc method, several SiO(2) films with different thicknesses were deposited on Si wafers, respectively, and their thermal conductivities were measured by both the dc method and 3ω method. The results of two methods are in good agreement within an acceptable error, and they are also inconsistent with some of previously published data.

In this paper, the ignition temperatures (Ti ) of seven kinds of coals were measured by using thermlgravimetric analyzer (TGA). A TG-DTG method was suggested to determine the ignition temperature. This method is simple, convenient, standardized and with high repeatability. The relations between Ti and volatile content and active energy are analyzed. Compared with the ignition temperatures measured in a bench scale fluidized bed and boiler test, Ti s derived from TG-DTG method have nearly same tendency with changing volatile content, but have 100°C deviation below those measured in fluidized bed. The results strongly indicate that TG-DTG method can substitute the fluidized bed method and boiler test for measuring ignition temperature of a coal with an off-set adjustment.Copyright © 2005 by ASME