bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemotherapy-Based Treatment for Castration-Resistant Prostate Cancer
Authors: Seruga Bostjan , Tannock Ian F.
Published: August 2011

Most men with metastatic prostate cancer respond to various types of androgen ablation but progress to castration-resistant disease. The TAX 327 and Southwest Oncology Group (SWOG) 99-16 clinical trials established docetaxel-based chemotherapy as preferred first-line treatment for most men with symptomatic metastatic castration-resistant prostate cancer (mCRPC). However, only about half receive benefit from docetaxel, and those who respond initially progress and eventually die of (or with) mCRPC. Both cellular mechanisms and the tumor microenvironment are implicated in the development of resistance to docetaxel. New agents are being evaluated for men with mCRPC, either as first-line treatment in combination with docetaxel, or in men progressing during or after treatment with docetaxel. Thus far, agents evaluated in phase III trials in combination with docetaxel have not improved outcome, including the vaccine GVAX, high-dose vitamin D (DN-101), and the antiangiogenic agent bevacizumab. In contrast, cabazitaxel, a taxane that is not cross-resistant to docetaxel, substantially improved the outcome of men progressing during or after treatment with docetaxel-based chemotherapy when compared with mitoxantrone and prednisone. However, translation of benefit of cabazitaxel demonstrated in the TROPIC (Treatment of Hormone-Refractory Metastatic Prostate Cancer) trial into general oncologic practice will be challenging because this agent may cause serious toxicity. With the approval of less toxic hormonal agents (eg, abiraterone acetate) in the setting of docetaxel-resistant mCRPC, clinicians will have an opportunity to balance benefits and harms of new agents in an individual patient and may be able to use different agents in sequence.
Environmental Accounting for Pollution in the United States Economy
Authors: Muller Nicholas Z , Mendelsohn Robert , Nordhaus William
Published: August 2011

This study presents a framework to include environmental externalities into a system of national accounts. The paper estimates the air pollution damages for each industry in the United States. An integrated-assessment model quantifies the marginal damages of air pollution emissions for the US which are multiplied times the quantity of emissions by industry to compute gross damages. Solid waste combustion, sewage treatment, stone quarrying, marinas, and oil and coal-fired power plants have air pollution damages larger than their value added. The largest industrial contributor to external costs is coal-fired electric generation, whose damages range from 0.8 to 5.6 times value added. (JEL E01, L94, Q53, Q56)
Segregation and the Quality of Government in a Cross Section of Countries
Authors: Alesina Alberto , Zhuravskaya Ekaterina
Published: August 2011

We provide a new compilation of data on ethnic, linguistic, and religious composition at the subnational level for a large number of countries. Using these data, we measure segregation of groups within the country. To overcome the endogeneity problem that arises because of mobility and endogenous internal borders, we construct an instrument for segregation. We find that more ethnically and linguistically segregated countries, i.e., those where groups live more spatially separately, have a lower quality of government; there is no relationship between religious segregation and governance. Trust is an important channel of influence; it is lower in more segregated countries. (JEL H11, H77, J15, O17, Z12, Z13)
Climbing atop the Shoulders of Giants: The Impact of Institutions on Cumulative Research
Authors: Furman Jeffrey L , Stern Scott
Published: August 2011

While cumulative knowledge production is central to growth, little empirical research investigates how institutions shape whether existing knowledge can be exploited to create new knowledge. This paper assesses the impact of a specific institution, a biological resource center, whose objective is to certify and disseminate knowledge. We disentangle the marginal impact of this institution on cumulative research from the impact of selection, in which the most important discoveries are endogenously linked to research-enhancing institutions. Exploiting exogenous shifts of biomaterials across institutional settings and employing a difference-in-differences approach, we find that effective institutions amplify the cumulative impact of individual scientific discoveries. (JEL D02, D83, I23, O30)
Esquire Mans the Kitchenette
Authors: fakazis elizabeth
Published: August 2011

In this article, I examine representations of masculinity and domestic cooking in Esquire's “Man the Kitchenette,” a cooking column for men published in the 1940s. Using qualitative content analysis, I examine how these representations recoded an interest in food and domestic cooking (as well as other traditionally “feminine” interests) as appropriately masculine, nurturing the development of the positive image of the “male consumer” and paving the way for the emergence of future men's lifestyle and culinary magazines.
Weed Populations, Sweet Corn Yield, and Economics Following Fall Cover Crops
Authors: O'Reilly Kelsey A. , Robinson Darren E. , Vyn Richard J. , Van Eerd Laura L.
Published: August 2011

The effectiveness of cover crops as an alternative weed control strategy should be assessed as the demand for food and fiber grown under sustainable agricultural practices increases. This study assessed the effect of fall cover crops on weed populations in the fall and spring prior to sweet corn planting and during sweet corn growth. The experiment was a split-plot design in a pea cover–cover crop–sweet corn rotation with fall cover crop type as the main plot factor and presence or absence of weeds in the sweet corn as the split-plot factor. The cover crop treatments were a control with no cover crop (no-cover), oat, cereal rye (rye), oilseed radish (OSR), and oilseed radish with rye (OSR+rye). In the fall, at Ridgetown, weed biomass in the OSR treatments was 29 and 59 g m−2lower than in the no-cover and the cereal treatments, respectively. In the spring, OSR+rye and rye reduced weed biomass, density, and richness below the levels observed in the control at Bothwell. At Ridgetown in the spring, cover crops had no effect on weed populations. During the sweet corn season, weed populations and sweet corn yields were generally unaffected by the cover crops, provided OSR did not set viable seed. All cover crop treatments were as profitable as or more profitable than the no-cover treatment. At Bothwell profit margins were highest for oat at almost Can$600 ha−1higher than the no-cover treatment. At Ridgetown, compared with the no-cover treatment, OSR and OSR+rye profit margins were between Can$1,250 and Can$1,350 ha−1and between Can$682 and Can$835 ha−1, respectively. Therefore, provided that OSR does not set viable seed, the cover crops tested are feasible and profitable options to include in sweet corn production and provide weed-suppression benefits.
Pyroxsulam Compared with Competitive Standards for Efficacy in Winter Wheat
Authors: Geier Patrick W. , Stahlman Phillip W. , Peterson Dallas E. , Claassen Mark M.
Published: August 2011

Field studies at six locations over 3 yr in Kansas compared pyroxsulam at two application timings to competitive standards for winter annual weed control in winter wheat. Pyroxsulam applied fall-POST (FP) controlled downy brome 84 to 99% and was similar to or greater than sulfosulfuron, propoxycarbazone, or propoxycarbazone plus mesosulfuron. Downy brome control was lower when application timing was delayed until spring (SP), such that no herbicide provided more than 90% downy brome control. Cheat control was 97% or more with almost all herbicides applied FP, and greater than 90% in most locations when herbicides were applied SP. Sulfosulfuron was the exception with only 30 to 81% cheat control. All FP-applied herbicides, except sulfosulfuron at Manhattan, KS, controlled blue mustard 95% or more. Pyroxsulam and propoxycarbazone plus mesosulfuron FP completely controlled henbit at Hesston, KS, in 2009, but no herbicide treatment provided more than 60% control when applied SP. Averaged over application timings, pyroxsulam provided the greatest henbit control (76 and 78%) at Manhattan and Hays, respectively, in 2009, and FP treatments were 33 and 28 percentage points more effective than SP treatments at those locations. Averaged over application timing, wheat yields did not differ between herbicide treatments in five of six locations. Averaged over herbicide treatment, FP-treated wheat yielded more grain than SP-treated wheat at three of the six locations.
Greenhouse Assessment of Differences in Clomazone Tolerance among Sweetpotato Cultivars
Authors: Harrison H. F. , Jackson D. M.
Published: August 2011

Differences in clomazone tolerance among sweetpotato cultivars were first observed in April 2007 after use of the herbicide for weed control in fields containing the sweetpotato breeding project at the U.S. Vegetable Laboratory. Susceptible cultivars and experimental clones exhibited severe foliar chlorosis and reduced growth, whereas the most tolerant were not injured. Twelve cultivars and experimental clones were included in a greenhouse experiment to quantify the differences in clomazone tolerance. In the greenhouse, the clomazone concentration that caused moderate injury or reduction in shoot growth to the most tolerant clones was approximately 10 times the concentration that caused a similar response in the most susceptible clones. Two older cultivars, Excel and Sumor, that were developed before the registration of clomazone for use in sweetpotato were susceptible. Clomazone is an important component in sweetpotato weed management, and susceptibility is an undesirable trait that should be avoided in new sweetpotato cultivars.
Quantification of Warm-Season Turfgrass Injury from Triclopyr and Aminocyclopyrachlor
Authors: Flessner Michael L. , McElroy J. Scott , Wehtje Glenn R.
Published: August 2011

Synthetic auxin herbicides are widely used because of their effective control of broadleaf weeds and safety in many turfgrass species. However, two synthetic auxin herbicides, triclopyr and aminocyclopyrachlor (AMCP; DPX-KJM44), are known to injure warm-season turfgrasses. Our objective was to quantify this injury through evaluations of turfgrass quality and turfgrass green cover in response to herbicide treatment. The results of this study indicate that relative to the labeled use rates of triclopyr (0.56 to 1.12 kg ae ha−1) and AMCP (0.053 kg ai ha−1), zoysiagrass is the only turfgrass tested with sufficient tolerance to the respective compounds for their use as weed-control agents. Bermudagrass and centipedegrass may be injured by triclopyr and AMCP at labeled rates, characterized by a reduction in turfgrass quality and green cover. St. Augustinegrass is not tolerant of either triclopyr or AMCP at labeled rates.
Confirmation, Control, and Physiology of Glyphosate-Resistant Giant Ragweed (Ambrosia trifida) in Arkansas
Authors: Norsworthy Jason K. , Riar Dilpreet , Jha Prashant , Scott Robert C.
Published: August 2011

Glyphosate-resistant giant ragweed in Arkansas was reported in 2005. A study was conducted to (1) confirm and characterize the glyphosate resistance in giant ragweed, (2) determine if reduced absorption or translocation is the mechanism of glyphosate resistance in giant ragweed, and (3) evaluate the efficacy of nine POST-applied soybean herbicides to control glyphosate-resistant and -susceptible giant ragweed. Based on the rate required to kill 50% of plants (LD50values), resistant giant ragweed biotypes from Greene and Jefferson counties were 2.3- to 7.2-fold less sensitive to glyphosate compared to susceptible biotypes. Glyphosate absorption and translocation for glyphosate-resistant and -susceptible biotypes was similar at 24 and 72 h after treatment. Thus, differential absorption or translocation is not a mechanism of glyphosate resistance in this resistant giant ragweed biotype. Control of resistant giant ragweed biotypes with glyphosate at a labeled field application rate of 840 g ha−1was only 60% or less compared to complete control of a susceptible giant ragweed biotype. However, bentazon, carfentrazone, cloransulam, and fomesafen controlled both biotypes more than 95%.
When Does Institutional Investor Activism Increase Shareholder Value?: The Carbon Disclosure Project
Authors: Kim Eun-Hee , Lyon Thomas
Published: August 2011

This paper presents the first empirical test of the financial impacts of institutional investor activism towards climate change. Specifically, we study the conditions under which share prices are increased for the Financial Times (FT) Global 500 companies due to participation in the Carbon Disclosure Project (CDP), a consortium of institutional investors with $57 trillion in assets. We find no systematic evidence that participation, in and of itself, increased shareholder value. However, by making use of Russia’s ratification of the Kyoto Protocol, which caused the Protocol to go into effect, we find that companies’ CDP participation increased shareholder value when the likelihood of climate change regulation rose. We estimate the total increase in shareholder value from CDP participation at $8.6 billion, about 86% of the size of the carbon market in 2005. Our findings suggest that institutional investor activism towards climate change can increase shareholder value when the external business environment becomes more climate conscious.
Promoting Physical Activity in Individuals With Diabetes: Telehealth Approaches
Authors: Mori DeAnna L. , Silberbogen Amy K. , Collins Allison E. , Ulloa Erin W. , Brown Kirstin L. , Niles Barbara L.
Published: August 2011

“Health is the vital principle of bliss, and exercise, of health.” —James Thomson, 18th century Scottish poet

Exercise is considered a crucial component of disease management for individuals with type 2 diabetes, and it is associated with extensive health and mental health benefits. Although the benefits of exercise are well established, most people with diabetes do not engage in physical activity in a regular and sustained manner. To address this, it is important to develop interventions that are easily and broadly accessible and that address specific barriers that prevent individuals with diabetes from participating in physical activity. Several investigations have examined the efficacy of using various forms of technology to deliver or enhance interventions designed to promote regular physical activity. The outcomes have been promising, providing support for continued exploration of telehealth interventions that promote physical activity in the diabetic population. This article provides an overview of telephone, Internet-based, and home-based monitoring interventions that promote physical activity, with a focus on those with diabetes. It also discusses the potential advantages of using telehealth interventions in this context.
Bioactive (3Z,5E)-11,20-Epoxybriara-3,5-dien-7,18-olide Diterpenoids from the South China Sea Gorgonian Dichotella gemmacea
Authors: Li Cui , La Ming-Ping , Sun Peng , Kurtan Tibor , Mandi Attila , Tang Hua , Liu Bao-Shu , Yi Yang-Hua , Li Ling , Zhang Wen
Published: August 2011

Six new (3Z,5E)-11,20-epoxybriara-3,5-dien-7,18-olide diterpenoids, gemmacolides N–S (1–6), were isolated together with four known analogues, juncenolide D, and juncins R, S and U (7–10), from the South China Sea gorgonian Dichotella gemmacea. The structures of the new compounds were elucidated by the detailed analysis of spectroscopic data in combination with the comparison with reported data. The absolute configuration of 1 was determined by a TDDFT calculation of its solution ECD spectrum, affording the determination of absolute configuration of other analogues by simply comparing their ECD spectra with that of 1. The cytotoxic and antimicrobial activities of these compounds were evaluated. In preliminary in vitro bioassays, compounds 4, 5, 6, 8 and 9 showed cytotoxicity against A549 and MG63, while compounds 1, 2, 4, 7–10 showed antimicrobial activity against the fungus Septoria tritici and the bacterium Escherichia coli.
Synthesis of New Riminophenazines with Pyrimidine and Pyrazine Substitution at the 2-N Position
Authors: Zhang Gang , Zhang Hao , Wang Xiaojian , Li Chun , Huang Haihong , Yin Dali
Published: August 2011

New riminophenazines with pyrimidine and pyrazine substituents at the 2-position were successfully synthesized. The key step is the 2-N-arylation of riminophenazines with pyrimidine and pyrazine. The optimized reaction conditions involve the use of a Pd2(dba)3/DPPF/Cs2CO3/toluene combination.
Une révolution (trop) tranquille ?
Authors: Schmid Peter F. , Zeller Odile
Published: August 2011

Résumé Près de 70 ans après son apparition, l’Approche centrée sur la personne (ACP) fait preuve de sa vitalité à l’échelle planétaire, entre autres via une pratique diversifiée et créative ainsi que via divers développements théoriques – dans le droit fil de l’esprit de son fondateur, qui appelait à un développement continuel ainsi qu’à un examen critique de l’ACP. Plus il y a de nouvelles sous-orientations et de perspectives se réclamant de l’ACP et se comptant parmi « la famille », de méthodes se revendiquant de l’ACP, de diversité, plus se pose également la question des critères : quelles sont les caractéristiques déterminantes ? Qu’est-ce qui est, au sein de ces modalités multiformes, unique en son genre dans l’ACP ? Cet article cherche à répondre à ce questionnement en recourant aux notions fondamentales de personne, de processus d’actualisation, de rencontre, de groupe et de dialogue (avec des références bibliographiques permettant d’aller plus loin). La problématique de l’identité et des critères d’identification de l’approche est indissolublement liée à son rôle actuel dans le champ psychosocial, dans la société et en politique ainsi qu’à la question de savoir si nous exploitons sa richesse et son potentiel de manière suffisamment conséquente 1 .
Structural and Psychological Empowerment and Reflective Thinking: Is There a Link?
Authors: Lethbridge Kristen , Andrusyszyn Mary-Anne , Iwasiw Carroll , Laschinger Heather K. S. , Fernando Rajulton
Published: August 2011

Baccalaureate nursing education prepares students to become registered nurses in evolving health care systems. During their program, students’ perceptions of empowerment in the nursing profession begin to form, and they are introduced to the process of reflective thinking. The purpose of this integrative literature review is unique in that three concepts are examined and linked—structural empowerment (as conceptualized by Kanter), psychological empowerment (as described by Spreitzer), and reflective thinking (as characterized by Mezirow)—and a theoretical model for testing is proposed. In examining the conceptual links, it is apparent that all three are required for learning and nursing practice. By preparing students to be empowered, reflective professionals, it is proposed that they will be more effective in their academic and future practice work. The conceptual links and proposed model described in this article provide the foundation for building a body of evidence to support or refute this contention.
Structure of an ambient vibration wavefield in the frequency range of engineering interest ([0.5, 20] Hz): insights from numerical modelling
Authors: Albarello Dario , Lunedei Enrico
Published: August 2011

The expected structure of an ambient vibration wavefield at the top of a shallow soft layer overlying a rigid bedrock is explored by applying a full wavefield physical model, under the hypothesis that ambient vibrations are the effect of a uniform distribution of random independent point‐like harmonic sources at the surface of a flat, weakly dissipative Earth. The comparison of the results provided by this model with those deduced on the assumption that surface waves dominate the wavefield allows evaluation of the respective roles of body and surface waves (Love and Rayleigh) in their fundamental and higher modes. This analysis reveals that the structure of the ambient vibration wavefield strongly depends on the subsoil structure (P‐ and S‐wave velocity profiles and thickness of the uppermost soft sedimentary layer) and on the distribution of ambient vibration sources around the receiver. This dependence also changes along with the frequency range of interest. In this regard, three frequency domains are identified, each showing a different sensitivity to the relevant parameters: below the fundamental resonance frequency for S‐waves
, above the frequency
, where
is the resonance frequency for P‐waves and in‐between. A consequence that emerges is that a number of possible combinations of body and surface waves are possible, which could account for the heterogeneous results obtained from experimental studies. These findings also indicate constraints on the use of simplified models based on the assumption that surface waves dominate the ambient vibration wavefield, as is currently the case in most engineering applications.
Study on Design and Simulation of the Vibration-Reduction of the Damp Structure for the Gearbox
Authors: Wang Xin , Fu Jin Bo , Yin Xun Min
Published: August 2011

The study on design and simulation of reduce vibration are carried out of the damp structure for the simulative experimental gear case to reduce vibration and noise of the ship gearbox. Multiple projects are designed for the gear case of the damp structure on the basis of the structure characteristic of the gearbox. The finite element analyze computation is carried out of box of gear case under the different project of the damp and the different damp material. The fine damp material and the optimization structure parameters of damp will be ascertained by the analysis of mode and frequency response. The contrastive analysis of vibration and noise is carried out for the box of fore-and-aft treat of damp structure. The analytical result indicates that the vibration and noise of gearbox will be reduced observably when the project of damp is adopted.
Preload Design of Bearings in Helicopter Transmission System
Authors: Yin Mei , Qiu Jun Peng , Gao Jie
Published: August 2011

In order to reduce running noise and enhance the stiffness and accuracy of shaft guidance, the bearings often use preload design in some position of the helicopter transmission system. In addition, the preload design of the bearings can compensate for wear in the operation and provide long service life of the bearings. By expatiating on the effect, types, determination and adjustment procedure, it offers reference for the design of preload for bearings.
Optimal Design of Passive Magnetic Damper for Rotor Based on Sequential Quadratic Programming Method
Authors: Zuo Cong Yang , Zhou Jin
Published: August 2011

In a high-speed rotor system, vibration control is necessary to ensure steady operation of the system. Magnetic damper is one of the effective means to control the vibration. This paper is concerned with the optimal design of a passive magnetic damper’s system parameter, including its geometric and electrical parameters. The relation between the damper’s system parameter and its damping coefficient is derived. A mathematical model that maximizes the damping coefficient is built, with the constraints of the geometric and electrical parameters. The optimization program is based on the algorithm of sequential quadratic programming method. The program yields the maximum damping coefficient under the given condition of the rotor’s diameter.
A Static and Dynamic Model of Spiral Bevel Gears
Authors: Wang Jing , Alves Joël Teixeira , Guingand Michèle , de Vaujany Jean Pierre , Velex Philippe
Published: August 2011

Two three-dimensional lumped parameter dynamic models of spiral bevel gears are presented and compared. The first approach is classic and relies on a single averaged mesh stiffness element connecting the gears whereas a time-varying non-linear distribution of discrete stiffness elements over the potential contact area is used in the second model.
Helicopter Transmission System Technology Readiness Assessment
Authors: Liu Jian Wu , Wang Shuai , Wang Yong Hong
Published: August 2011

This paper states evaluative methods of technology readiness which are used in the national background projects development. The methods conduct helicopter transmission system technology maturity research and assessment of native significant project according to methods of technology readiness assessment. The conclusions indicate that methods of technology readiness assessment have very important promoting action to native project development and scientific decision-making. The project which adopts mature critical technology implies that guarantee the schedule of project development and reduce risk of project development. Actualizing assess methods of technology readiness can be an important part of project development risk management.
A Challenge to Design of a New Harmonic Drive Device
Authors: Li Shu Ting
Published: August 2011

A new silk-hat type of harmonic drive device (HDD) with arc flexspline (FS) structure is developed. Loaded gear contact analysis (LGCA) and stress calculations are made for it with three-dimensional, finite element method (3D-FEM). Basic performances and strengths tests are also made. It is found that the new structure almost has the same performances and strength as the old one.
Effects of Graphite Content on Performance of Powder Injection Molding Copper-Based Antifriction Materials
Authors: Qiao Bin , Xiao Lei , Shang Feng , Li Hua Qiang , Guo Ting Liang
Published: August 2011

Copper-based antifriction materials were prepared by powder injection molding. The wear rate of the antifriction material and the coupled parts, and the friction coefficient were studied under the friction condition by changing the content of graphite from 2.5 % to 25%. The results show that the wear rate and the friction coefficient decrease with the increase of the graphite content when the content of graphite is less than 10%. When the content of graphite is 10%~15%, the friction coefficient can be kept stably at low levels(0.25), thereby better density and hardness can be obtained by reducing the consumption of antifriction material and coupled parts, which improves the antifriction effect and protects the coupled parts at the same time. When the content of the graphite is larger than 15%, the wear rate of the antifriction material goes up and the friction coefficient is increased.
Adaptive Impulse Controller Design of Harmonic Drives System with Friction
Authors: Li Gang Jun
Published: August 2011

The friction model with the effects of friction and transmission flexibility of harmonic drives system is used for adaptive impulse control design in precision control system. Experimental response based on a new pulse shape which is consisted of two harmonic expansions is studied, the first harmonic is the main pulse to drive the arm to move a displacement, the second harmonic has two functions: it enforces the main harmonic pulse in its first half that will help it to eliminate the dead zone, and provides a minus pulse in its second half to stop the arm motion quickly. An adaptive impulse feedback controller is developed based on it. Simulation and experiments show the effectiveness of the proposed controller, robustness of dead zone elimination to friction variation can be guaranteed.
Research on Milling-Turning Compound Processing of Spiral Bevel Gears Based on GibbsCAM
Authors: Tao Gui Bao , Yi Li Li , Zheng Zhi , Hu Lin Hua
Published: August 2011

By analyzing characteristics of the surface of spiral bevel gear, this paper introduces the key technologies of modeling, process planning and NC programming about milling-turning compound processing of spiral bevel gears based on GibbsCAM, these new methods can be used to produce one-piece or small batch of spiral bevel gears.
Modular Design on Basic Parameters of Volume Reducer
Authors: Wang Tie , Shen Jun , Zhao Fu Qiang
Published: August 2011

In order to meet high-volume, low-cost reducer and ensuring quality in the production of reducer, a new design method is necessary. This paper applies the design method of ‘modular’ in high-volume reducer production, preferred numbers and mechanical optimization design thought, then based on access database and VB programming software research modular design process of the volume reducer. Higher degree basic modular parameters of volume reducer are obtained.
An Accurate Modeling Method of the Plane Enveloping Hourglass Worm
Authors: Chen Xiao An , Tang Li Ming
Published: August 2011

This paper proposes a new method for creating the accurate 3D geometry model of the plane enveloping hourglass worm efficiently. The working tooth surfaces of the worm are enveloped by the mother plane surfaces. And according to the gear engagement theory, the equations of the surfaces enveloped are established. By combination with engineering practice, the geometrical features of the surface enveloped are analyzed, and one of its features is that it is a ruled surface consisted of countless straight lines which are contact lines. For ∑(u, Φ1), which represents the surface enveloped, let the variable u equals two values respectively, and two helix curves are gained. Connect the two curves with a ruled surface, and make sure that the ruled surface is consisted of contact lines. So the surface gained is a enveloped surface with no error existing in theory. Once the surfaces enveloped are gained, it’s easy to create the geometry model of the worm. Using UG, the paper provides an example showing how to create the worm’s model, and the new method and a past method are both used to create the model. The new method not only creates an accurate model, but also improves the efficiency. For example, at the time-consuming step for creating the surface enveloped, compared with the past method, the new method is able to save approximate 94% of the time.
Rolling Contact Fatigue Life of Case−Hardened Steel Treated by Shot Peenings with Shot Diameters of 0.05 mm and 0.30 mm
Authors: Wang Lei , Liu Guang Liang , Seki Masanori , Fujii Masahiro , Li Qian
Published: August 2011

In order to investigate the influence of different shot peenings on the rolling contact fatigue life of case−hardened steel, the thrust type rolling contact fatigue test was performed with a ball−on−disk contact tester. In this study, the case−hardened steel disks were treated by the fine particle peening with a shot diameter of 0.05 mm and the normal shot peening with a shot diameter of 0.30 mm. The surface hardness and the surface compressive residual stress of the test disks were increased by these peenings. On the other hand, the surface roughness of the test disks was increased by the normal shot peening, and was decreased by the fine particle peening. The rolling contact fatigue test showed that the rolling contact fatigue life of the test disks was improved by the fine particle peening, and was not improved by the normal shot peening. The rolling contact fatigue life of the test disks became longer as their surface roughness became smaller. Therefore, it follows from this that the fine particle peening, which can provide the increase in surface hardness and the decrease in surface roughness, is good for the increase in the rolling contact fatigue life of case−hardened steel.
Determination of Load-Sharing Displacement of Flexible Pin Roll in Planet Gear Train
Authors: Zhang Yue Chun , Tan Liang , Liu Ping , Zhou Hong Bo
Published: August 2011

The eccentricity errors of each piece in the planet gear train set are described. This paper has made a tentative study on the determination of load-sharing displacement with formulas of equivalent errors. It takes the flexible pin roll as the load-sharing piece and LevelⅡ planet gear drive in the speed-increasing gearbox of some wind power generator for the case study. The results show i) that the radial error of each piece does not influence the operation of the planet gear train, but the tangential error does influence the load-sharing among the planet gears; and ii) that the load sharing displacement is determined by the centering tangential equivalent error of the flexible pin roll, which may provide reference to projects.
Research on Gear Contact Fatigue Stress Test
Authors: Wang Tie , Li Hong Mei , Zhang Rui Liang , Wu Zhi Fei
Published: August 2011

This paper put forward the rapid measure method of the gear contact fatigue stress value with a few gear samples, which can get the estimated value of the gear fatigue limit value precisely and rapidly. And the gear fatigue life curve and fatigue damage accumulation curve are simulated by MATLAB. Comparing with the traditional test method, this method can reduce the cost and save the time.
A Method to Determine the Basic Value of Gear Root Stress Based on FEM
Authors: Zhang Jian , Wu Hong Cai , Wang Hong Jie
Published: August 2011

In order to improve the case that the safety margin is a little higher using GB3480 to determine the gear root stress, a method which combines the GB3480 and FEM to determine the basic value of gear root stress is proposed. Using FEM, the comprehensive gear root stress can be figured out firstly based on the accurate tooth profile model. Then the gear root stress can be determined more accurately according to the key coefficients. Using the proposed method, the basic value of the gear root stress for the gears given in this paper is decreased by 11%. The proposed method can provide the useful guide to lightweight design for the gear transmission system.
Effects of Surface Roughness and Abnormal Surface Layer on Fatigue Strength
Authors: Deng Gang , Suzuki Syohei , Nakanishi Tsutomu
Published: August 2011

The purpose of this research is to evaluate the effects of surface roughness in normalized steel and the effects of abnormal surface layer in carburized steel on the fatigue strength that is considered as the limit of no crack initiation. Normalized and Carburized test pieces with crowned round notches were used in the fatigue tests, the normalized test pieces have different surface roughnesses and the carburized test pieces have different surface microstructures on the notch surface. The changes in fatigue strength due to the differences in the notch surface roughness and surface microstructure were investigated. As the conclusions, fatigue strength will be certainly increased by decreasing the surface maximum height, and removing the abnormal surface layer formed during carburized treatment leads to a marked increase in fatigue strength.
Manufacturing of Aerospace Parts with Diffusion Bonding Technology
Authors: Lee Ho Sung , Yoon Jong Hoon , Yoo Joon Tae
Published: August 2011

The objective of this study is to manufacture aerospace components with diffusion bonding technology. Examples produced with this technology consist of thin-sheet diffusion bonding and massive diffusion bonding. The mechanism of diffusion bonding process was presented with schematic microstructure development. Aerospace parts include titanium tanks and a scaled combustion chamber with bonded steel and copper. The microstructure of bonded region shows no indication of heterogeneous phases at interface. It is shown that the diffusion bonding of aerospace materials was successfully performed to manufacture lightweight aerospace parts.
Properties of TaN Coating Film Deposited on WC-Co-Based Cemented Carbide Using Magnetron Sputter Ion Plating
Authors: Wada Tadahiro , Iwamoto Koji , Tsukamoto Keizo , Hiro Kazuki
Published: August 2011

Various methods of surface modification technology are available for yielding high function characteristics such as wear-resistance, lower or higher friction coefficient, corrosion-resistance and thermal-resistance on the surface of the material. Generally, the coating of a hard material like ceramic on the surface of a material is a popular surface modification technology. The physical vapor deposition (PVD) method, which is one of the coating technologies, is widely used because it can be coated at a lower treatment temperature of 470K – 870K. In cutting, e.g. turning, milling, drilling and tapping, coated cemented carbide tools, which have good fracture toughness and wear resistance, seem to be effective tool materials. In this case, the titanium based films (e.g. TiN, Ti(C,N), (Ti,Al)N) are generally used as the coating film. However, the tantalum based films (e.g. TaN, TaC) are not applied as the coating film for cutting tools because the melting point of TaC is higher than that of TiC. Moreover, it is unclear whether TaN coating film can be used as a coating film of WC-Co cemented carbide cutting tools. In this study, to clarify the effectiveness of tantalum (TaN) coating film, we measured the thickness, hardness and scratch strength (critical load measured by scratch tester) of TaN coating film formed on the surface of the substrate which was a cemented carbide ISO K10 by the magnetron sputter ion plating process. The hardened steel ASTM D2 (JIS SKD11) was turned with the TaN and the (Ti,Al)N coated cemented carbide tools. The tool wear of the TaN coated cemented carbide tool was experimentally investigated and compared with that of the (Ti,Al)N coated tool. The following results were obtained: (1) Droplets on the surface of the TaN coating film, which has the K10 substrate, were negligible. (2) The micro-hardness of TaN coating film 2510HV was higher than that of TiN coating film 2090HV, and there was little difference in hardness between the TaN 2510HV and (Ti,Al)N 2710HV. (3) The critical scratch load of TaN coating film over 130N was higher than that of TiN coating film 68N or (Ti,Al)N coating film 73N. (4) In cutting the hardened steel using TaN and (Ti,Al)N coated tools, the wear progress of the TaN coated carbide tool was almost equivalent to that of the (Ti,Al)N coated carbide tool. The above results clarify that the TaN coating film, which is a new type of coating film, has both high hardness and good adhesive strength, and can be used as a coating film of WC-Co cemented carbide cutting tools.
High-Precision Moment of Inertia Testing System and Error Analysis
Authors: Zhang Ai Jun , Cheng Xiao Lin , Pan Wen Song
Published: August 2011

Pointed at low precision of great object’s moment of inertia, high-precision moment of inertia testing system is developed. Comparing with several measurement methods, we adopt method of torsion pendulum. We design mechanical structure and analyze error which is compensated in software. According to our experiment, precision of this system can achieve 5‰.
A Novel Identification Method of Rotor Time Constant of Induction Motor
Authors: Li Qiang , Yang Tong Guang
Published: August 2011

Vector control system is dependent of parameters of motor, and rotor time constant usually changes with temperature. Through analyzing the influence of rotor time constant variations on the control system performance, a novel identification method based on adaptive flux observer is presented. Different with traditional pole assignment method, it implies robust control theory and Lyapunov stability theory, by solving a linear matrix inequality (LMI) to obtain the feedback gain matrix. The simulation results show that this method can identify the rotor time constant of induction motor accurately, and it has rapid converge, good indiscrimination degree and strong robustness.
Mechanical Properties and Reinforcement Mechanism of Amorphous Particles Reinforced Aluminum Matrix Composites
Authors: Wang Jin Xiang , Zhao Rui Jin , Zhang Xiao Li
Published: August 2011

The metallic glass particles reinforced aluminum matrix composites without obvious defects were obtained successfully by explosive compaction of mixed powders. The quasi-static compressive mechanical properties of the composites with the reinforcement matrix mass fraction 10%, 15% and 20% respectively were researched recur to universal testing machine of Instron 3367 and self-consistent theory. Finally, reinforcement mechanism of the metallic glass particles on the matrix was analyzed by numerical simulation recur to LS-DYNA program. The results show that the mechanical properties obtained by self-consistent theory are well accord with the experimental results; compared with pure aluminum, the yield stress of the composites with metallic glass particles reinforcement of the mass fraction 20% enhances 46.8 percent; the main reinforcement mechanism is the amorphous particles can undertake higher loading, the combined quality of the reinforcement particles with the matrix and the distribute uniformity of the reinforcement particles are important factors which will affect the reinforcement effects.
Relationships of Strengths and Dimensional Effect of Plastic Concrete
Authors: Gao Dan Ying , Song Shuai Qi , Hu Liang Ming
Published: August 2011

This article carried out the strength experiments on four hundred and five specimens with twelve mix proportions and three curing ages, systematically investigated the relationships of related strengths, the dimensional effect of compressive strength and splitting tensile strength of plastic concrete. The results showed that there well exist the statistical relationships among the related strengths of plastic concrete, the dimensional effect coefficients of compressive strength and splitting tensile strength with 100mm cubic specimen are 0.9375 and 0.8616 respectively compared with 150mm cubic specimen. Based on the analysis of test results, the conversion formulae of strength-related indicators and linear function relationship between axial compressive strength and curing ages are put forward respectively.
Pore Structural Changes and Carbonated Depth of Carbonated Steel Slag
Authors: Wu Hao Ze , Chang Jun , Wang Hua
Published: August 2011

Steel slag and carbon dioxide were used as raw materials to prepare building material by carbonation. Effects of forming pressure on carbonation of steel slag and carbonated depth were studied by pore structural changes before and after carbonation and carbonated region. The results showed that these were visible pore structural changes between non-carbonated and carbonated steel slag, and after carbonation, the porosity of steel slag samples were decreased, the number of fine pore was increased and large pore was opposite. Carbon dioxide gas which was sequestrated by Ca(OH)2 and C3S were combined in CaCO3 crystal, and this process was form surface to interior. Clustered granular crystals were generated in the surface and 12 mm depth of samples, while none in the 20 mm depth of samples, no obvious granular crystal growth. The granular crystals which produced by carbonation filled the pores of the sample, in particular the arrangement of dense granular surface of crystal layer, which may impede the spread of CO2 gas to the depths, and carbonation reaction focused on the surface to 12 mm depth region.
Synthesis of Carbon/Carbon Core/Shell Nanofibers by Co-Pyrolysis of Tetrahydrofuran and Ferrocene
Authors: Kang Wen Jun , Li Hai Bo , Yan Yan , Qian Yi Tai
Published: August 2011

Carbon/carbon core/shell nanofibers with length up to several micrometres have been prepared by co-pyrolysis of tetrahydrofuran and ferrocene in a stainless steel autoclave at 600 °C. The diameter of carbon core is ~10 nm, and the thickness of carbon shell is ~20 nm. It is found that the graphene layers of carbon core are perpendicular to the ones of carbon shell in stacking orientation. Comparative experiments confirm that the metallic iron catalysts, originating from the decomposition of ferrocene, are responsible for the formation of nanofibers. When the ferrocene is absence, only solid carbon spheres are observed. Moreover, hollow hexapod-like carbon materials can be obtained with water introduced into reaction system.
Characterization of AB5-Type Metal Hydride Modified by Electroless Plating Nickel in Forming Process
Authors: Wu Wu Tsan , Do Jing Shan
Published: August 2011

Metal hydride (MH) alloy (MmNi3.81Mn0.41Al0.19Co0.76) is modified by the electroless nickel plating and used as the electroactive material of negative electrode in Ni/MH batteries. The effect of the concentrations of reductant (NaH2PO2×H2O), complex agent (Na3C6H5O7×2H2O), reaction time, and reaction temperature on the Ni loadings and the utilization of the modified MH are systematically studied. The experimental results reveal that the appropriate reaction time and temperature of electroless nickel plating are 30 min and 70 °C in this work. The loading amount of Ni-P on MH alloy is increased and decreased by increasing the concentration of reductant and complex agent, respectively. The steady utilization of unmodified MH alloy is 94.7±1.0 % in the forming process under the charge/discharge conditions of 0.2C charge to 160% SOC (state of charge) and 0.2C discharge to 0.95V. The utilization of MH alloys modified with conditions of [NaH2PO2×H2O] = 40 g L-1 and [Na3C6H5O7×2H2O] = 20 g L-1, T = 70 °C, t = 30 min and [MH] = 2g/100 ml, respectively, is improved to 101.9±0.3 %.
Electrodeposition of Au/Brush-Zn Heterojunction Nanowires
Authors: Zhao Xue , Wu Yong Zhong , Hao Xiao Peng
Published: August 2011

Au/brush-Zn heterojunction nanowires were synthesized by using the Anodic Alumina Membrane (AAM) template combine with DC electrodeposition. As-prepared Au/brush-Zn nanowires were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive x-ray spectrometer (EDS). Secondary growth mechanism is proposed for the formation of Zn brush structure. The Au/brush-Zn nanowires exhibit a strong absorption in a broad range of wavelength especially between 200 and 360nm, which may be ascribed to the transition of the electrons from the d band to the s, p conduction band near the Fermi surface and the transition from valence bands to conduction bands for Zn brush associated with enhancement of Au.
Experimental Research on Mechanical Properties of Coal Paste Filling Material
Authors: Zhao Cai Zhi , Zhou Hua Qiang
Published: August 2011

One new kind of cementitious material, which is suited to paste filling in coal mine, was introduced. The paste filling slurry, which is mixed with extremely small amount(about 50 kg/m3) of the material, can be solidified quickly and reach the strength requirement of none -village-relocation coal extraction engineering. The solidified body is provided with typical plasticity, high elastic modulus and strain hardening even under the condition of very small surrounding stress.
Synthesis and Application of an Efficient and Stable Solid Acid Catalyst St-c-AS
Authors: Liu Sheng Huan , Meng Ping Rui , Yu Li Juan , Zhang Yan Mei , Wang Xiao Hui
Published: August 2011

Styrene/Sodium allyl sulfonate copolymer (St-c-SAS) were prepared using soap-free emulsion polymerization method and boiling at high-speed stirring, and it was acided to obtain an efficient, stable, reusable new solid acid catalyst styrene/acrylic acid copolymer (St-c-AS). Elemental analysis and acid–base titration techniques showed that St-c-AS have high concentration of sulfonic groups. Differential thermal analysis (DTA) and thermogravimetric analysis (TG) results showed that the sulfonic of copolymer was hard to fall off at high temperature. Esterifications of acetic acid with ethanol showed that St-c-AS has high catalytic activity, and the catalyst can be reused without separation of 10 times, the esterification yields close to or exceed 100%. The superior performance of St-c-AS is attributed to their unique features including large surface area, high content of sulfonic groups as well as high temperature resistance.