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Simultaneous Improvement (simultaneous + improvement)

Distribution by Scientific Domains

Polymers and Materials Science	37%

Selected Abstracts

Ultralow Dielectric Constant Tetravinyltetramethylcyclotetrasiloxane Films Deposited by Initiated Chemical Vapor Deposition (iCVD)

ADVANCED FUNCTIONAL MATERIALS, Issue 4 2010
Nathan J. Trujillo
Abstract Simultaneous improvement of mechanical properties and lowering of the dielectric constant occur when films grown from the cyclic monomer tetravinyltetramethylcyclotetrasiloxane (V4D4) via initiated chemical vapor deposition (iCVD) are thermally cured in air. Clear signatures from silsesquioxane cage structures in the annealed films appear in the Fourier transform IR (1140,cm,1) and Raman (1117,cm,1) spectra. The iCVD method consumes an order of magnitude lower power density than the traditional plasma-enhanced CVD, thus preserving the precursor's delicate ring structure and organic substituents in the as-deposited films. The high degree of structural retention in the as-deposited film allows for the beneficial formation of intrinsically porous silsesquioxane cages upon annealing in air. Complete oxidation of the silicon creates ,Q' groups, which impart greater hardness and modulus to the films by increasing the average connectivity number of the film matrix beyond the percolation of rigidity. The removal of labile hydrocarbon moieties allows for the oxidation of the as-deposited film while simultaneously inducing porosity. This combination of events avoids the typical trade-off between improved mechanical properties and higher dielectric constants. Films annealed at 410,°C have a dielectric constant of 2.15, and a hardness and modulus of 0.78 and 5.4,GPa, respectively. The solvent-less and low-energy nature of iCVD make it attractive from an environmental safety and health perspective. [source]

Measurement of management efforts with respect to integration of quality, safety, and ergonomics issues in manufacturing industry

HUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 2 2005
John S. Dzissah
The main objective of this study was to identify critical factors that measure management efforts with regard to quality, safety, and ergonomics issues for their simultaneous improvement. Eleven identified management activity areas have been synthesized from the literature as the most important areas that meet all stakeholders' needs. Factors were then developed to measure the efficiency of these activities through a questionnaire. The overall response rate of the survey questionnaire was 47%. The reliability coefficients ranging from 0.73 to 0.85 indicated that some scales or management activity areas are more reliable in measuring potential for improvements in terms of quality, ergonomics, safety, and efficiency. The proposed instrument for quantifying management efforts with respect to simultaneous improvements in the areas of quality, ergonomics, and safety was found to be valid and reliable. © 2005 Wiley Periodicals, Inc. Hum Factors Man 15: 213,232, 2005. [source]

Genetic parameters for dry matter, energy and protein intake, and their relationships with performance and carcass traits in Japanese Black cattle

JOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 1 2009
M.A. Hoque
Summary Genetic parameters for feed intake and performance traits of 514 bulls and carcass traits of 22 099 of their progeny, and the relationships of measures of feed intake with performance and carcass traits were estimated. Feed intake traits were dry matter intake (DMI), concentrate intake (CONI), roughage intake, ratio of roughage intake to DMI, metabolizable energy intake (MEI) and digestible crude protein intake (DCPI). Performance traits included daily gain, metabolic weight, live weight at the end of test, dry matter conversion ratio and residual feed intake. Progeny carcass traits were carcass weight, percentage of meat yield, rib eye area (REA), subcutaneous fat, marbling score, meat colour (MCS), fat colour (FCS) and meat quality grade. All the feed intake and performance traits were moderately heritable. The heritabilities for REA and MCS were moderate, and that for FCS was low, while those for the other carcass traits were high. Selection against DMI, CONI and DCPI would reduce excessive intake of feed, but would have undesirable effects on growth and most of the carcass traits. Selection against MEI would lead to improvements in feed efficiency and growth traits. Selection against DCPI would also improve feed efficiency; however, responses in growth traits would decrease. Results indicate that selection against MEI might be better than any other measures of feed intake to improve feed efficiency with simultaneous improvement in growth and most of the carcass traits. [source]

Structure, Morphology and Properties of a Novel Molecular Composite by In-Situ Blending of Anionic Polyamide 6 with a Polyamide Copolymer Containing Rigid Segments

MACROMOLECULAR MATERIALS & ENGINEERING, Issue 2 2007
Xiaochun Wang
Abstract Molten caprolactam, in which a polyamide copolymer (HPN) containing rigid segments was dissolved, was polymerized by means of anionic ROP to in produce polyamide (PA, nylon) 6 blends with HPN in situ. A novel molecular composite was achieved in which toughness and strength were simultaneously improved, as well as modulus, compared to virgin PA6. In view of the interchange reaction between PA6 and PA1212 (and PA66) in blends fabricated in the same way, it was deduced that a similar reaction between PA6 and HPN took place during the blending and led to copolymerization between the two components. The formation of copolymers was verified by their single glass transition and single melting peak, measured through DMA and DSC, respectively. DSC analysis also showed that the occurrence of the interchange reaction inhibited the crystallization and suppressed the melting point of PA6. Analysis by FT-IR spectroscopy indicated that the difference in the distance between the amide groups for PA6 and HPN induced a decrease in the amount and strength of hydrogen bonding. Moreover, characterization by POM and XRD revealed that the spherulite size of the PA6 crystals decreased dramatically and the amount of , crystal increased slightly with the majority of crystallites being , crystals. Furthermore, it was found through the observation of the morphology by SEM that no phase separation existed in the composites. On the basis of detailed analysis and a comparison between the in situ PA6/PA66 and PA6/HPN blends, it is believed that the combination of markedly decreasing spherulite size and similar segmental mobility resulted in the simultaneous improvement of mechanical properties for the in situ PA6/HPN blends. [source]

Simultaneously improving the toughness, flexural modulus and thermal performance of isotactic polypropylene by ,-, crystalline transition and inorganic whisker reinforcement

POLYMER ENGINEERING & SCIENCE, Issue 2 2010
Yewen Cao
Magnesium salt (M-HOS) whisker and ,-nucleating agent were introduced into polypropylene and their effects on the crystalline structures, morphologies, mechanical properties, and thermal resistance of polypropylene (PP) were investigated. The results of wide angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), and polar optical microscopy (POM) examinations suggested that the presence of the whisker did not cause any negative effect on the occurrence of ,-modification, and ,-phase became absolutely dominant form in ,-nucleated samples. The mechanical and thermal properties tests demonstrated that there is an excellent synergy between the ,-nucleating agent and the whisker. For PP composite containing 0.1 wt% of the ,-nucleating agent and 10 wt% of the whiskers, the Izod notched impact strength, elongation at break, flexural modulus, and heat deflection temperature were increased by 108, 194, 31, and 40%, respectively, compared with those of neat PP. By combining the toughening effect of ,,, transition with the reinforcing effect of the whisker, simultaneous improvement in toughness, flexural modulus, and thermal performance of PP was successfully achieved. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers [source]

Measurement of management efforts with respect to integration of quality, safety, and ergonomics issues in manufacturing industry

Re-refinement from deposited X-ray data can deliver improved models for most PDB entries

ACTA CRYSTALLOGRAPHICA SECTION D, Issue 2 2009
Robbie P. Joosten
The deposition of X-ray data along with the customary structural models defining PDB entries makes it possible to apply large-scale re-refinement protocols to these entries, thus giving users the benefit of improvements in X-ray methods that have occurred since the structure was deposited. Automated gradient refinement is an effective method to achieve this goal, but real-space intervention is most often required in order to adequately address problems detected by structure-validation software. In order to improve the existing protocol, automated re-refinement was combined with structure validation and difference-density peak analysis to produce a catalogue of problems in PDB entries that are amenable to automatic correction. It is shown that re-refinement can be effective in producing improvements, which are often associated with the systematic use of the TLS parameterization of B factors, even for relatively new and high-resolution PDB entries, while the accompanying manual or semi-manual map analysis and fitting steps show good prospects for eventual automation. It is proposed that the potential for simultaneous improvements in methods and in re-refinement results be further encouraged by broadening the scope of depositions to include refinement metadata and ultimately primary rather than reduced X-ray data. [source]

Child abuse in South Africa: rights and wrongs

CHILD ABUSE REVIEW, Issue 2 2008
Linda M. Richter
Abstract In a country in which human rights feature prominently in our discourse about who we are, as well as in the South African constitutional and legal framework, so many wrongs continue to be done to children. One category of wrongs is abuse, but it is not the only one. Poverty, patriarchy and gender violence, as well as the socialised obedience, dependency and silence of women and children, create conditions in which abuse can occur, often with few consequences. South Africa has extremely high rates of both physical and sexual abuse of children. Progressive, rights-based legislation exists to protect children, but it is not adequately supported or resourced by services to fulfil their provisions. Child abuse and neglect will not be significantly reduced in South Africa, without simultaneous improvements in the social and economic conditions in which very large numbers of children live. Copyright © 2008 John Wiley & Sons, Ltd. [source]