bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthetic Strategy and Anti-Tumor Activities of Macrocyclic Scaffolds Based on 4-Hydroxyproline
Authors: Cao Guorui , Yang Kun , Li Yue , Huang Longjiang , Teng Dawei
Published: February 2016

A series of novel 13- to 15-member hydroxyproline-based macrocycles, which contain alkyl-alkyl ether and alkyl-aryl ether moieties, have been synthesized by the strategy of macrocyclization utilising azide-alkyne cycloaddition, Mitsunobu protocol and amide formation. Their anti-tumor activities towards A549, MDA-MB-231 and Hep G2 cells were screened in vitro by an MTT assay. The results indicated that 13-member macrocycle 33 containing alkene chain showed the best results, exhibiting the highest inhibitory effects towards lung cancer cell line A549, which was higher than that of the reference cisplatin (IC50 value = 2.55 µmol/L).
Micronutrient Fortified Condiments and Noodles to Reduce Anemia in Children and Adults—A Literature Review and Meta-Analysis
Authors: Hess Sascha , Tecklenburg Linda , Eichler Klaus
Published: February 2016

Micronutrient deficiencies impose a considerable burden of disease on many middle and low income countries. Several strategies have been shown to be effective in improving micronutrient deficiencies. However, the impact of fortified condiments as well as fortified noodles is less well documented. We aimed to investigate existing evidence on the impact of micronutrient fortified condiments and noodles on hemoglobin, anemia, and functional outcomes in children and adults (age: 5 to 50 years). We conducted a literature review in electronic databases. In addition, we screened the homepages of relevant organizations and journals. We included randomized controlled trials (RCT). Of 1046 retrieved studies, 14 RCT provided data for the meta-analysis. Micronutrient fortification of condiments and noodles increased hemoglobin concentrations by 0.74 g/dL (95%-confidence intervals (95%-CI): 0.56 to 0.93; 12 studies) and 0.3 g/dL (95%-CI: 0.12 to 0.48; 1 study), respectively. Micronutrient fortification also led to a reduced risk of having anemia (risk ratio 0.59 (95%-CI 0.44 to 0.80)). Ferritin concentrations increased with fortified condiments. Functional outcomes were rarely assessed and showed mixed results. The use of micronutrient fortified condiments can be a strategy to reduce anemia in children and adults due to micronutrient deficiencies. The effect of fortified noodles seems to be smaller.
SrTiO3 Nanocube-Doped Polyaniline Nanocomposites with Enhanced Photocatalytic Degradation of Methylene Blue under Visible Light
Authors: Shahabuddin Syed , Muhamad Sarih Norazilawati , Mohamad Sharifah , Joon Ching Juan
Published: February 2016

The present study highlights the facile synthesis of polyaniline (PANI)-based nanocomposites doped with SrTiO3 nanocubes synthesized via the in situ oxidative polymerization technique using ammonium persulfate (APS) as an oxidant in acidic medium for the photocatalytic degradation of methylene blue dye. Field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), UV–Vis spectroscopy, Brunauer–Emmett–Teller analysis (BET) and Fourier transform infrared spectroscopy (FTIR) measurements were used to characterize the prepared nanocomposite photocatalysts. The photocatalytic efficiencies of the photocatalysts were examined by degrading methylene blue (MB) under visible light irradiation. The results showed that the degradation efficiency of the composite photocatalysts that were doped with SrTiO3 nanocubes was higher than that of the undoped polyaniline. In this study, the effects of the weight ratio of polyaniline to SrTiO3 on the photocatalytic activities were investigated. The results revealed that the nanocomposite P-Sr500 was found to be an optimum photocatalyst, with a 97% degradation efficiency after 90 min of irradiation under solar light.
Combining On-Line Characterization Tools with Modern Software Environments for Optimal Operation of Polymerization Processes
Authors: Ghadipasha Navid , Geraili Aryan , Romagnoli Jose , Castor Carlos , Drenski Michael , Reed Wayne
Published: February 2016

This paper discusses the initial steps towards the formulation and implementation of a generic and flexible model centric framework for integrated simulation, estimation, optimization and feedback control of polymerization processes. For the first time it combines the powerful capabilities of the automatic continuous on-line monitoring of polymerization system (ACOMP), with a modern simulation, estimation and optimization software environment towards an integrated scheme for the optimal operation of polymeric processes. An initial validation of the framework was performed for modelling and optimization using literature data, illustrating the flexibility of the method to apply under different systems and conditions. Subsequently, off-line capabilities of the system were fully tested experimentally for model validations, parameter estimation and process optimization using ACOMP data. Experimental results are provided for free radical solution polymerization of methyl methacrylate.
The Added Value of Stratified Topographic Correction of Multispectral Images
Authors: Sola Ion , González-Audícana María , Álvarez-Mozos Jesús
Published: February 2016

Satellite images in mountainous areas are strongly affected by topography. Different studies demonstrated that the results of semi-empirical topographic correction algorithms improved when a stratification of land covers was carried out first. However, differences in the stratification strategies proposed and also in the evaluation of the results obtained make it unclear how to implement them. The objective of this study was to compare different stratification strategies with a non-stratified approach using several evaluation criteria. For that purpose, Statistic-Empirical and Sun-Canopy-Sensor + C algorithms were applied and six different stratification approaches, based on vegetation indices and land cover maps, were implemented and compared with the non-stratified traditional option. Overall, this study demonstrates that for this particular case study the six stratification approaches can give results similar to applying a traditional topographic correction with no previous stratification. Therefore, the non-stratified correction approach could potentially aid in removing the topographic effect, because it does not require any ancillary information and it is easier to implement in automatic image processing chains. The findings also suggest that the Statistic-Empirical method performs slightly better than the Sun-Canopy-Sensor + C correction, regardless of the stratification approach. In any case, further research is necessary to evaluate other stratification strategies and confirm these results.
Does Business Model Affect CSR Involvement? A Survey of Polish Manufacturing and Service Companies
Authors: Witek-Hajduk Marzanna , Zaborek Piotr
Published: February 2016

The study explores links between types of business models used by companies and their involvement in CSR. As the main part of our conceptual framework we used a business model taxonomy developed by Dudzik and Witek-Hajduk, which identifies five types of models: traditionalists, market players, contractors, distributors, and integrators. From shared characteristics of the business model profiles, we proposed that market players and integrators will show significantly higher levels of involvement in CSR than the three other classes of companies. Among other things, both market players and integrators relied strongly on building own brand value and fostering harmonious supply channel relations, which served as a rationale for our hypothesis. The data for the study were obtained through a combined CATI and CAWI survey on a group of 385 managers of medium and large enterprises. The sample was representative for the three Polish industries of chemical manufacturing, food production, and retailing. Statistical methods included confirmatory factor analysis and one-way ANOVA with contrasts and post hoc tests. The findings supported our hypothesis, showing that market players and integrators were indeed more engaged in CSR than other groups of firms. This may suggest that managers in control of these companies could bolster the integrity of their business models by increasing CSR involvement. Another important contribution of the study was to propose and validate a versatile scale for assessing CSR involvement, which showed measurement invariance for all involved industries.
Mycotoxin Contamination in the EU Feed Supply Chain: A Focus on Cereal Byproducts
Authors: Pinotti Luciano , Ottoboni Matteo , Giromini Carlotta , Dell’Orto Vittorio , Cheli Federica
Published: February 2016

Mycotoxins represent a risk to the feed supply chain with an impact on economies and international trade. A high percentage of feed samples have been reported to be contaminated with more than one mycotoxin. In most cases, the concentrations were low enough to ensure compliance with the European Union (EU) guidance values or maximum admitted levels. However, mycotoxin co-contamination might still exert adverse effects on animals due to additive/synergistic interactions. Studies on the fate of mycotoxins during cereal processing, such as milling, production of ethanol fuels, and beer brewing, have shown that mycotoxins are concentrated into fractions that are commonly used as animal feed. Published data show a high variability in mycotoxin repartitioning, mainly due to the type of mycotoxins, the level and extent of fungal contamination, and a failure to understand the complexity of food processing technologies. Precise knowledge of mycotoxin repartitioning during technological processes is critical and may provide a sound technical basis for feed managers to conform to legislation requirements and reduce the risk of severe adverse market and trade repercussions. Regular, economical and straightforward feed testing is critical to reach a quick and accurate diagnosis of feed quality. The use of rapid methods represents a future challenge.
Are microsatellite fragment lengths useful for population‐level studies? The case of Polygala lewtonii (Polygalaceae)
Authors: Germain‐Aubrey Charlotte C. , Nelson Cory , Soltis Douglas E. , Soltis Pamela S. , Gitzendanner Matthew A.
Published: February 2016

Premise of the study:

Microsatellites, despite being commonly used population‐level markers, contain biases because scoring relies solely on fragment length. Their complexity can lead to homoplasy, the effects of which are poorly understood. We investigated the impact of using fragment lengths, repeats, or flanking region sequences on common population‐level analyses.

Methods:

Five polymorphic microsatellite markers amplified across the central Florida scrub endemic Polygala lewtonii (Polygalaceae) and its close, widespread congener P. polygama. We genotyped 147 individuals of P. lewtonii and 156 of P. polygama, and sequenced the amplicons of four markers across all individuals. We ran basic statistics, spatial clustering analysis, historical demographics, and migration tests.

Results:

One population of intermediate morphology was genetically clearly identified as P. polygama, making it the southernmost population of this species. Statistics were comparable between the fragment length and repeat numbers, with some notable differences. Flanking regions exhibited surprisingly high polymorphism between species, and between geographically distant conspecific populations.

Discussion:

The increasing use of markers developed in one species and amplified in another is only a good practice if precautions are taken, notably the sequencing of the fragments between species and populations. Flanking region sequences are a useful marker at the interspecific level.
Surface coating affects behavior of metallic nanoparticles in a biological environment
Authors: Jurašin Darija Domazet , Ćurlin Marija , Capjak Ivona , Crnković Tea , Lovrić Marija , Babič Michal , Horák Daniel , Vinković Vrček Ivana , Gajović Srećko
Published: February 2016

Silver (AgNPs) and maghemite, i.e., superparamagnetic iron oxide nanoparticles (SPIONs) are promising candidates for new medical applications, which implies the need for strict information regarding their physicochemical characteristics and behavior in a biological environment. The currently developed AgNPs and SPIONs encompass a myriad of sizes and surface coatings, which affect NPs properties and may improve their biocompatibility. This study is aimed to evaluate the effects of surface coating on colloidal stability and behavior of AgNPs and SPIONs in modelled biological environments using dynamic and electrophoretic light scattering techniques, as well as transmission electron microscopy to visualize the behavior of the NP. Three dispersion media were investigated: ultrapure water (UW), biological cell culture medium without addition of protein (BM), and BM supplemented with common serum protein (BMP). The obtained results showed that different coating agents on AgNPs and SPIONs produced different stabilities in the same biological media. The combination of negative charge and high adsorption strength of coating agents proved to be important for achieving good stability of metallic NPs in electrolyte-rich fluids. Most importantly, the presence of proteins provided colloidal stabilization to metallic NPs in biological fluids regardless of their chemical composition, surface structure and surface charge. In addition, an assessment of AgNP and SPION behavior in real biological fluids, rat whole blood (WhBl) and blood plasma (BlPl), revealed that the composition of a biological medium is crucial for the colloidal stability and type of metallic NP transformation. Our results highlight the importance of physicochemical characterization and stability evaluation of metallic NPs in a variety of biological systems including as many NP properties as possible.
Enabling technologies and green processes in cyclodextrin chemistry
Authors: Cravotto Giancarlo , Caporaso Marina , Jicsinszky Laszlo , Martina Katia
Published: February 2016

The design of efficient synthetic green strategies for the selective modification of cyclodextrins (CDs) is still a challenging task. Outstanding results have been achieved in recent years by means of so-called enabling technologies, such as microwaves, ultrasound and ball mills, that have become irreplaceable tools in the synthesis of CD derivatives. Several examples of sonochemical selective modification of native α-, β- and γ-CDs have been reported including heterogeneous phase Pd- and Cu-catalysed hydrogenations and couplings. Microwave irradiation has emerged as the technique of choice for the production of highly substituted CD derivatives, CD grafted materials and polymers. Mechanochemical methods have successfully furnished greener, solvent-free syntheses and efficient complexation, while flow microreactors may well improve the repeatability and optimization of critical synthetic protocols.
Fitting Noise Management Signal Processing Applying the American Academy of Audiology Pediatric Amplification Guideline: Verification Protocols
Authors: Scollie Susan , Levy Charla , Pourmand Nazanin , Abbasalipour Parvaneh , Bagatto Marlene , Richert Frances , Moodie Shane , Crukley Jeff , Parsa Vijay
Published: February 2016

Background:Although guidelines for fitting hearing aids for children are well developed and have strong basis in evidence, specific protocols for fitting and verifying some technologies are not always available. One such technology is noise management in children’s hearing
aids. Children are frequently in high-level and/or noisy environments, and many options for noise management exist in modern hearing aids. Verification protocols are needed to define specific test signals and levels for use in clinical practice.Purpose:This work aims to (1) describe
the variation in different brands of noise reduction processors in hearing aids and the verification of these processors and (2) determine whether these differences are perceived by 13 children who have hearing loss. Finally, we aimed to develop a verification protocol for use in pediatric
clinical practice.Study Sample:A set of hearing aids was tested using both clinically available test systems and a reference system, so that the impacts of noise reduction signal processing in hearing aids could be characterized for speech in a variety of background noises. A second
set of hearing aids was tested across a range of audiograms and across two clinical verification systems to characterize the variance in clinical verification measurements. Finally, a set of hearing aid recordings that varied by type of noise reduction was rated for sound quality by children
with hearing loss.Results:Significant variation across makes and models of hearing aids was observed in both the speed of noise reduction activation and the magnitude of noise reduction. Reference measures indicate that noise-only testing may overestimate noise reduction magnitude compared
to speech-in-noise testing. Variation across clinical test signals was also observed, indicating that some test signals may be more successful than others for characterization of hearing aid noise reduction. Children provided different sound quality ratings across hearing aids, and for one
hearing aid rated the sound quality as higher with the noise reduction system activated.Conclusions:Implications for clinical verification systems may be that greater standardization and the use of speech-in-noise test signals may improve the quality and consistency of noise reduction
verification cross clinics. A suggested clinical protocol for verification of noise management in children’s hearing aids is suggested.
Análise perspectiva da dicotomia entre qualidade de vida no trabalho e produtividade: percepção de gestores
Authors: Bortolozo Eliana Aparecida Fagundes Queiroz , Dos Santos Celso Bilynkievycz Bilynkievycz , De Menezes Fábio Sprada , Pilatti Luiz Alberto , Xavier Antonio Augusto De Paula
Published: February 2016

OBJETIVO: Conhecer a percepção do gestor, especificamente do profissional engenheiro, no tocante aos reflexos dos Programas de Qualidade de Vida no Trabalho (PQVTs).

MÉTODOS: Trata-se de um estudo exploratório. Para a coleta de dados foi construído e validado um instrumento que avalia a percepção de profissionais gestores quanto aos principais benefícios da implantação de um PQVT. Foi adotado o procedimento da amostragem aleatória simples, abrangendo 30 engenheiros, e a pesquisa desenvolveu as etapas do processo de aquisição de conhecimento em base de dados (knowledge discovery in databases - KDD). Para testar o modelo e, a partir da sua taxa de acerto, foram utilizadas técnicas de data mining de cluster.

RESULTADOS: O estudo constatou que apenas 16,66% dos gestores proporcionam algum PQVT em suas empresas, o que revela um descompasso entre as novas tendências da relação do mundo do trabalho e a efetividade de tais programas. Dos gestores entrevistados, 13,00% consideraram no máximo sete reflexos positivos dos PQVTs e apontaram, de forma mais frequente no rol de suas próprias prioridades, a diminuição do absenteísmo, o aumento da produtividade e da lucratividade.

CONCLUSÕES: Observa-se que, de modo geral, na implantação de um PQVT, a produtividade é considerada uma variável dependente, sendo a diminuição do absenteísmo e a lucratividade suas variáveis intervenientes, a ela associadas. Estes dados demonstram que, do ponto de vista dos gestores, não é possível pensar numa efetiva qualidade de vida no trabalho (QVT) dissociada da produtividade.
Entrevista com Wagner Wey Moreira
Authors: Pilatti Luiz Alberto
Published: February 2016

Wagner Wey Moreira possui doutorado em Educação (Psicologia Educacional) e Livre Docência pela Universidade Estadual de Campinas (UNICAMP). Foi um dos criadores da Faculdade de Educação Física da UNICAMP. Publicou e organizou mais de uma dezena de livros, alguns já com elevado número de edições, entre eles Educação Física e Esportes: perspectivas para o século XXI e Qualidade de Vida: complexidade e educação. Já orientou 69 mestrados e 14 doutorados. Atualmente é professor da Universidade Federal do Triangulo Mineiro (UFTM).
Immunochip Analyses of Epistasis in Rheumatoid Arthritis Confirm Multiple Interactions within MHC and Suggest Novel Non-MHC Epistatic Signals
Authors: Wei Wen-Hua , Loh Chia-Yin , Worthington Jane , Eyre Stephen
Published: February 2016

Objective.

Studying statistical gene-gene interactions (epistasis) has been limited by the difficulties in performance, both statistically and computationally, in large enough sample numbers to gain sufficient power. Three large Immunochip datasets from cohort samples recruited in the United Kingdom, United States, and Sweden with European ancestry were used to examine epistasis in rheumatoid arthritis (RA).

Methods.

A full pairwise search was conducted in the UK cohort using a high-throughput tool and the resultant significant epistatic signals were tested for replication in the United States and Swedish cohorts. A forward selection approach was applied to remove redundant signals, while conditioning on the preidentified additive effects.

Results.

We detected abundant genome-wide significant (p < 1.0e-13) epistatic signals, all within the MHC region. These signals were reduced substantially, but a proportion remained significant (p < 1.0e-03) in conditional tests. We identified 11 independent epistatic interactions across the entire MHC, each explaining on average 0.12% of the phenotypic variance, nearly all replicated in both replication cohorts. We also identified non-MHC epistatic interactions between RA susceptible loci LOC100506023 and IRF5 with Immunochip-wide significance (p < 1.1e-08) and between 2 neighboring single-nucleotide polymorphism near PTPN22 that were in low linkage disequilibrium with independent interaction (p < 1.0e-05). Both non-MHC epistatic interactions were statistically replicated with a similar interaction pattern in the US cohort only.

Conclusion.

There are multiple but relatively weak interactions independent of the additive effects in RA and a larger sample number is required to confidently assign additional non-MHC epistasis.
Recurrent Pediatric Perianal Swelling
Authors: Cordova Jonathan , Chugh Ankur , Rivera Rivera Edgardo D. , Young Sona
Published: February 2016

Pediatric inflammatory bowel disease is a chronic gastrointestinal disease consisting of Crohn's disease (CD) and ulcerative colitis (UC). Both disease processes can share similar clinical symptoms including abdominal pain, diarrhea, hematochezia, and weight loss; CD can also be complicated by penetrating and fistulizing disease. Perianal skin tags, perianal abscesses, recto-cutaneous fistulae, and rectal stenosis are among the phenotypic characteristics of perianal CD. Current treatment strategies are focused on the surgical drainage of abscesses and the closure of fistulous tracts as well as controlling intestinal inflammation with the use of immunomodulators (6-mercaptopurine and methotrexate) and biologics (infliximab and adalimumab). Current guidelines by the American Gastroenterology Association and the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition recommend a combination of surgical intervention and medical management for the treatment of perianal CD.

[
Pediatr Ann
. 2016;45(2):e59–e62.]
A Nanny Versus Daycare: Is There a Right Choice?
Authors: Kimball Valerie
Published: February 2016

As spring is on the horizon, my children begin to anticipate the end of the school year with thoughts of sleeping in, free days at the pool, and long evenings outside with friends. I, too, look forward to this time of the year, and a much needed hiatus from coaxing kids out of bed, making school lunches, and homework help in the evenings. However, I do not look forward to finding a new “kid sitter” for my preteens and teenager. Choice of childcare is perceived as perhaps one of the most stressful decisions parents must make for their children. Pediatic caregivers should discuss childcare as early as the prenatal visit and at all well visits thereafter.

[
Pediatr Ann
. 2016;45(2):e36–e38.]
Eosinophilic Esophagitis: The “Not-So-Rare” Disease
Authors: Goh Vi Lier
Published: February 2016

Eosinophilic esophagitis (EoE) is a relatively newly described disorder with increasing incidence. Patients with EoE may present at all ages from childhood through adulthood. Presenting symptoms may vary from feeding refusal, gagging, and/or vomiting in the younger population, dysphagia, chest pain, and abdominal pain in adolescents, as well as emergent food impactions. However, there are strict diagnostic criteria that must be met to make the diagnosis. Specifically, the diagnosis of EoE requires at least 15 eosinophils per high-powered field in the esophageal biopsies and symptoms of esophageal dysfunction after other causes, such as gastroesophageal reflux disease and proton pump inhibitor-responsive esophageal eosinophilia, have been ruled out. Common treatments include diet modifications and/or topical corticosteroids.

[
Pediatr Ann
. 2016;45(2):e63–e66.]
Vascularization of Irregular Retinal Pigment Epithelial Detachments in Chronic Central Serous Chorioretinopathy Evaluated With OCT Angiography
Authors: de Carlo Talisa E. , Rosenblatt Amir , Goldstein Michaela , Baumal Caroline R. , Loewenstein Anat , Duker Jay S.
Published: February 2016

BACKGROUND AND OBJECTIVE:

To assess eyes with flat, irregular retinal pigment epithelial detachments (RPEDs) associated with central serous chorioretinopathy (CSCR) for choroidal neovascularization (CNV) using optical coherence tomography angiography (OCTA).

MATERIALS AND METHODS:

Retrospective review of OCTA images of chronic CSCR eyes with irregular RPED (group 1) and regular RPED (controls, group 2) for presence of CNV, subretinal fluid, and intraretinal fluid. Fluorescein angiography was also evaluated for CNV.

RESULTS:

CNV was detected using OCTA in 13 of 31 eyes (41.9%) in group 1 and in one of 18 eyes (5.6%) in group 2 (
P
= .007). Irregular RPED was a risk factor for CNV (odds ratio [OR] = 12.28; 95% CI, 1.45–104.3). There was no significant difference between detection by OCTA and FA (
P
= 1.0). Sensitivity and specificity of detection by OCTA were 85.7% and 95.7%, respectively.

CONCLUSIONS:

Irregular RPEDs in chronic CSCR eyes may harbor neovascularization more often than previously thought, which has implications on therapy.

[
Ophthalmic Surg Imaging Laser Retina
. 2016;47:128–133.]
Spontaneous Resolution of Large Macular Retinoschisis in Enhanced S-Cone Syndrome
Authors: Hayashi Takaaki , Gekka Tamaki , Tsuneoka Hiroshi
Published: February 2016

The authors previously reported details on enhanced S-cone syndrome (ESCS) in a 23-year-old male patient with a homozygous
NR2E3
mutation (p.Q350X) who developed large bilateral macular retinoschisis. Subsequent optical coherence tomography follow-up showed that although the large bilateral macular retinoschisis remained at the age of 28, there was dramatic improvement in the retinoschisis by the age 32, with bilateral resolution of the macular retinoschisis without any treatment by the age of 34. Although there is no established treatment for macular retinoschisis complicated by ESCS, this case demonstrated that intervention may not be required in some patients with ESCS.

[
Ophthalmic Surg Lasers Imaging Retina
. 2016;47:187–190.]
ANÁLISE PRELIMINAR DE VIABILIDADE HÍDRICA PARA INSTALAÇÃO DE UMA PEQUENA CENTRAL HIDRELÉTRICA: RIO LIGEIRO, CIANORTE, PR
Authors: Okawa Cristhiane Michiko Passos , De Oliveira Mennara Maria Dias , Roveri Silas Daniel
Published: February 2016

O estudo de Pequenas Centrais Hidrelétricas (PCH’s) é importante em um país rural e agrícola como o Brasil, especialmente na região do noroeste do Paraná. A possibilidade de que pequenos e médios agricultores possam usar a energia hídrica disponível nos rios próximos às suas terras gera impactos na economia da região de estudo, pois os beneficiados poderão dividir os gastos com a implantação e manutenção da PCH e depender, ao menos em parte, da geração de energia proveniente apenas da disponibilidade hídrica da região. O objetivo desse estudo é verificar a possibilidade de instalação de uma PCH no rio Ligeiro localizado próximo à cidade de Cianorte-PR, do ponto de vista hidrológico. A partir de dados de vazões médias diárias, foi determinada a curva de permanência de vazões e foram adotados os demais parâmetros, como eficiência de conversão da energia hidráulica em mecânica de 80% e demanda de energia futura fixa (não variando com o horizonte de projeto) de 1 MW. A mínima altura da barragem para atender a demanda foi calculada e comparou-se com o método de índice de gradiente (RDE) que relaciona a extensão do rio com sua altitude, para verificar se existe gradiente RDE suficiente para a altura determinada. Conclui-se que a disponibilidade hídrica da região de estudo e a topografia são suficientes para atender a uma demanda futura de energia fixada em 1MW.
On the Factors Influencing the Liquidity of Slip Casting Al2O3 Slurry
Authors: Geng Zhen Hua , Li Kai , Wu Ping , Li Hai Jian
Published: February 2016

Abstract: This paper use zeta potential test and dynamic viscosity test to research the influence of different factors such as pH value, mass fraction of solid phase and dispersant content on the liquidity of Al2O3 slurry. The test results show that, when the solid-phase mass fraction and particle size are given, the absolute value of zeta potential increases with the rise of pH value, raise at first then descrease with the adding of (NaPO3)6. This article analyzes the phenomena from a legal point of electric double layer effect. The results of liquidity test are consistent with zeta potential test. The optimum value of pH value, mass fraction of solid-phase and dispersant content are determined by formulation design. The study develop a Al2O3 slurry with high fluidity which has an important significant in slip casting process of Al2O3 ceramics.
Thermal Stability of Aluminum Titanate Ceramics
Authors: Li Hai Jian , Shao Xiao Shuang , Li Kai , Geng Zhen Hua , Wu Ping
Published: February 2016

The thermal stability of aluminum titanate (AT) ceramics is the main problem that restricted its extensive applications in many fields. In this paper, AT ceramics doped with single or composite additives of MgO, SiO2, mullite were fabricated by solid phase synthesis method. The thermal stability was tested by heated for 50h at 1100°C, and the phases of the samples were tested by X-ray diffraction (XRD) , and the microstructure were tested by SEM. The mechanism of the thermal stability of AT with additive was discussed based on DSC/TGA and electron back scatter diffraction pattern (EBSP). The results show that the adding of composite additives can improve the thermal stability of AT ceramics.
Synthesis and Characterization of LiZn Ferrites/Carbon Nanotubes (CNTs) Temperature Control Biomaterials
Authors: Liu Zhao Jun , Sun Kang Ning , Li Ai Min , Sun Xiao Ning , Zhang Shu Pin
Published: February 2016

In this study, LiZn ferrites with different content of CNTs (1%-9%) were successfully prepared by a sol-gel method. X-ray diffraction pattern exhibit a relatively high crystallinity of the Li0.25Zn0.5Fe2.25O4/CNTs composite, and the CNTs still exist after acid treatment and subsequent heat treatment. Then the composite was characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM), the results demonstrate that the particles are nearly spherical in shape and agglomerated to some extent. By a sol-gel method and subsequent calcination, the temperature of LiZn ferrites/CNTs temperature control biomaterials gradually increase and maintain at a certain temperature in the alternating magnetic field, so it can be a potential material used for hyperthermia applications.
Synthesis of Pyrochlore-Type K2Ta2O6 with High Photocatalytic Activity for Dye Degradation
Authors: Ma Ting Ting , Zhou Rui Shen , Li Xia
Published: February 2016

Pyrochlore-type potassium tantalate (K2Ta2O6 ) was successfully synthesized through a facile hydrothermal method. X-Ray diffraction and electron microscopy reveal that pure K2Ta2O6 consisting of a nanooctahedral structure could be obtained at 180°C for 24 h. The photocatalytic activities of K2Ta2O6 were examined using aqueous solutions under ultraviolet irradiation. The degradation result of the Rhodamine B dye indicated that the pyrochlore-type potassium tantalates exhibited a remarkably higher photocatalytic activity than the perovskite phase sample. This high photocatalytic activity is ascribed to both the high position of the conduction band and the high separation efficiency of electron-hole pairs of the pyrochlore structure.
Investigation on Properties of the Silica Ceramic Cores for the Hollow Blades Prepared by the Conversion of the Silicon Resin
Authors: Yu Jian Bo , Yang Zhi Gang , Li Chuan Jun , Deng Kang , Ren Zhong Ming
Published: February 2016

The working conditions of the ceramic cores are extremely harsh with the development of the preparation technology and improvement of the use conditions in the hollow blades, which brings forward high request for the preparation and properties of the ceramic cores. In this paper, silica ceramic powders were firstly coated by the silicon resin. The obtained composite powders were used to prepare the ceramic cores by the dry pressing method. And the phase compositions, microstructure and properties of the ceramic cores with the sintering temperatures were investigated. The results showed that the composite powders prepared by the coating showed good formability. The sintering temperature promoted the formation of the cristobalite. With the increase of the sintering temperature, the porosity of ceramic cores gradually decreased, the shrinkage rate and bulk-density increased. The prepared ceramic cores at 1250°C had highest bend strength of 19.25Mpa.
Effect of Amphoteric Zn2+ on the Determination of B2O3 Content in Glass
Authors: Bai Yong Zhi , Guan Hong Yan , Cui Jin Hua
Published: February 2016

The amphoteric ZnO can affect the titration of B2O3 content in glass since the Zn2+ will react with standard NaOH solution during the acid-base titration process and the result will be slightly higher sequentially. In this paper, the elimination of amphoteric Zn2+ was carried out by means of carbonate and Zn (OH)2 precipitation method. Results show that the optimal pH value for Zn (OH)2 precipitation is between 9~10. Verification test under borosilicate glass standard substance indicates that this method shows great applicability and accuracy in the determination of B2O3 content in Zn containing glass.
A Study of Environmental Impact Assessment on Intrinsic Energy and Full Life Cycle of Typical Energy-Saving Exterior Windows
Authors: Zhao Chun Zhi , Liu Yi , Jiang Quan , Ren Shi Wei
Published: February 2016

This paper established a set of localized intrinsic energy and full life-cycle environmental impacts of database for exterior windows. It deeply surveys and analyzes the non-renewable resource consumption (ADP), non-renewable energy consumption (PED), influence of greenhouse effect (GWP), acidification effect (AP), eutrophication (EP) and inhalable inorganics (RI) closely related national energy conservation policy objectives. These lay the foundation for intrinsic energy of buildings. Meanwhile, It discusses contributions of various exterior windows for energy consumption of buildings, which is conducive to using of green building materials and realization of green buildings.
Effect of ZrO2 Additive on the Properties of MgO-Cr2O3 Refractory Used for RH Degasser
Authors: Peng Chao , Yang Wei Bo
Published: February 2016

To improve the properties and RH degasser slag corrosion resistance of magnesia-chrome refractory, the effect of the addition of ZrO2 was investigated. The results showed that the presence ZrO2 additive can densify the magnesia-chrome samples due to promotion of grain boundary activities and ultimately direct bond formation, which improved the high temperature mechanical properties and corrosion resistance. The results also indicated that in the RH degasser slag system with a high ratio of calcia to silica, the slag resistance behavior of magnesia-chrome composite added ZrO2 could be described as follows: the ZrO2 reacts with CaO to form the calcium zirconate compound which is densification lay and simultaneously, could increase corrosion resistance performance by blinding pore and thickening slag viscosity. Therefore, it is expected to be the major reason for the ZrO2 enhanced corrosion resistance behavior observed for magnesia-chrome refractory.
A Facile and Reliable Preparing Route of Brown Fused Alumina from Aluminum Dross
Authors: Zhang Jun , Li Hua Bo , Duan Yong Hua
Published: February 2016

Aluminum dross is the staple solid waste in electrolytic aluminum industry. Taking full advantage of the aluminum dross is of great significance for controlling environmental pollution and saving resource. In this work, brown fused alumina is successfully prepared using aluminum dross as raw material through different pretreatments for aluminum dross. The results show that the brown fused alumina product is comprised of α-Al2O3 (ca.95%), NaCl (ca.1~3%) and CaF2 (ca.1~3%), and contents of the other components are as follows: MgO 0.33%, SiO2 1.12%, Fe2O3 0.41%, CaO 0.58%, TiO2 0.13%, K2O 0.05%, Na2O 0.87% and V2O5 0.92%. This quality of the resulting brown fused alumina can fully meet the national standards of China (GB/T 2478-2008).
Research on High Temperature Creep Properties of Al2O3-SiO2 Ore (Al2O3 ~ 65)
Authors: Sun Yong Qiang , Li Yong , Cao Shuo , Zhang Hao Bo , Gao Chang He , Zhang Ji Li
Published: February 2016

High temperature creep properties of Al2O3-SiO2 ore (65% Al2O3 by mass percentage, abbreviation for Al2O3~65) was studied. The results show that the creep rates at 1300 °C × 50h, 1400 °C × 50h and 1500 °C × 50h were-0.89% ,- 1.75%, - 5.76%,respectively. At 1300 °C, ore has good creep resistance. As the temperature increases, the high temperature creep resistance of Al2O3 ~ 65 bauxite ore is significantly reduced. Creep process can be divided into two stages: when the time t <30h, the sample are in the densification process; after 30 hours, the creep properties show that the relationship between time and the creep rate is linear. At 1300 °C, the absolute value which is the slope of the linear relationship is smaller, exhibited an excellent high-temperature creep resistance. The loading softening-temperature of Al2O3 ~ 65 bauxite ore is 1343 °C. The Sample phase and microstructure are characterized by X-ray diffraction and scanning electron microscopy (SEM). The results show that mullite reticular is formed in sample at 1300 °C; at this point, TiO2 mostly exist as Rutile. At 1400 °C and 1500 °C, TiO2 mostly exist as Aluminum titanate, Corundum phase portion into mullite.
Investigation on High-Temperature Creep Properties of High-Alumina Bauxite
Authors: Cao Shuo , Li Yong , Sun Jia Lin , Zhang Hao Bo , Sun Yong Qiang , Li Yan Jing , Gao Chang He , Zhang Ji Li
Published: February 2016

This paper studied the high temperature creep properties of high-alumina bauxite (the mass fraction of Al2O3 in the new ore is about 78, the following abbreviations for Al2O3~78). The results indicated that the Al2O3~78 high-alumina bauxite mainly are corundum phase after high temperature sintered.When the temperature is 1100°C, corundum exists as crystal phase and the connections between grains are directly. The creep resistance of samples is very good at this temperature and the creep rate of 50 hours heat preservation is-0.266%. When the temperature is 1200°C, liquid phase starts to produce in a large number and the creep rate in 50 hours heat preservation is-1.589%. When the temperature is 1300°C, because of the further increase on the amount of liquid phase and wetting coated corundum particle, the direct connections between corundum particles are broken and the creep resistance is greatly reduced, the creep rate in 50 hours heat preservation is-4.088%. The creep curve fitting after 25 hours indicated that the creep property shows linear relations in three different temperatures after 25 hours. When the temperature is 1200°C and 1300°C, the creep variables arise rapidly in linear which declare the creep resistance of corundum is poor and increasing with temperature go up, more corundum phase is covered by glass phase and the creep resistance reduces dramatically.
Analysis of the Effect of Interferometer Cavity Distortion on Homogeneity Tests of Large-Diameter Optical Materials
Authors: Shao Zhu Feng , Jia Ya Nan , Xiang Zai Kui , Wang Yu Fen , Sui Mei , Wang Jia Jia , Bao Yi Wang
Published: February 2016

Optical homogeneity of the optical materials directly affects the wavefront quality of the refractive optical system. There are some difficulties of testing large caliber optical materials, four-step method of Fizeau interferometry is a convenient and accurate method for measuring optical homogeneity. The article used the four-step method test the same quartz glass sample in a cavity with different precision and found that the optical homogeneity test results have a larger gap. While this article compared the effect of the fixed cavity surface shape and the changing cavity surface shape on 300 mm diameter quartz glass optical homogeneity test and analyzed the effect of different positions of fixed cavity distortion on optical homogeneity testing.
Effect of Heat-Treatment on Microstructure and Mechanical Properties of Magnesium Phosphate Cement
Authors: Tao Xin , Liu Jia Chen , Wang Ming Chao
Published: February 2016

Magnesium phosphate cement with M/P of 6, borax content of 4.8 wt% and water-to-cement ratio of 0.12, were made in this study. Heat-treatment was conducted from 200 °C to 1200 °C, and the physical and chemical evolution in the process of heating up was investigated via TG/DSC, XRD and SEM. Besides, the compressive strength, density and porosity of the heat-treated specimen were measured and the influence of treating temperature was discussed. The results show that magnesium phosphate cement possesses good chemical stability at 1200 °C and the strength has reduced only by 32.2% compared with none-treating specimens.
Greenhouse Effect Reduction through Sustainable Magnesium Oxide Eco-Cement Products
Authors: Yao Wu , Yang Yu Kun , Wu Meng Xue
Published: February 2016

Portland cement production leads to significant carbon dioxide emission and greenhouse effect. Magnesium oxide eco-cement, which is a mixture of Portland cement, magnesium oxide and fly ash, may be an alternative production. In this paper, the issue is focused on the carbon dioxide absorption ability and mechanical performance of this eco-cement. Several mix proportions of eco-cement were designed to conduct forced carbonation, strength and expansion tests. Also, microstructure analysis after carbonation was conducted. The results indicate that magnesium oxide eco-cement can efficiently absorb carbon dioxide and carbonation can improve mechanical performance substantially, also expansion of the eco-cement is found to fall within the safe limits and possesses good stability and soundness.
Study on the Threshold Value and Test Methods for Chloride Ion Content in Sea Sand
Authors: Sun Fei Long , Wu Shuai , Jiang Quan , Liu Ting Ting
Published: February 2016

The building sand is mainly composed of river sand at early stage. Recently, with the depletion of river sand, the new mined river sand cannot meet the demands for building sand. The sea sand is resourceful and can remedy the deficiency of sand for construction. However, the sea sand contains high content of chlorine salt, shell and lightweight matters. They are harmful for the strength and durability of concrete and will lead to premature corrosion of rebar. This will endanger the safety of construction. The studies demonstrate that high content of chlorine salt in sea sand is the main factor led to the deterioration of sea sand concrete. Therefore, in order to ensure the safety of construction, the threshold value of chloride content is specified in standards about concrete and aggregate. And methods testing the content of chloride ions are provided. However, the criterion in different standards differs from one another, which means their different viewpoints about the harm of chloride ions. In this work, the threshold value and test methods of chloride ion content for the building sand in the national standards and the international standards are summarized. The research has great significant for setting standards about sea sand, determining the rational threshold value of chloride ion content and improving the method testing the content of chloride ions.
A New Method for Studying the Damage in Concrete Subjected Single Face Salt Freezing Cycle
Authors: Li Wei Hong , Wang Yi Han , Bao Yi Wang , Yang Zong Ming
Published: February 2016

Aiming at the shortcomings of traditional research method of materials mechanics performance of concrete, this paper presents a new method to test the mechanical properties of concrete material layer body--the relative method. It focuses on the use of relative principle, testing dynamic elastic modulus of concrete damage layer subjected to single salt freezing cyclic, and draw a gradient damage curve of concrete, and then study the damage process of the concrete under the effect of salt solution and the freeze-thaw cycle synergetic factors. The method provides a new way to test body layer mechanical performance of concrete material which the traditional methods can not be directly solved.
Characteristics of Metallurgical Waste Slag and its Heating Behavior in a Microwave Field
Authors: Li Qi Nan , Ma Guo Jun , Zhang Xiang , Cai Xun
Published: February 2016

Four kinds of typical metallurgical waste slags were characterized with their chemical composition, crystalline phases, microstructure and thermal behavior. The heating behavior of these slags in a microwave field were also examined. The results show that there is a high content of CaO in these waste slags. When the metallurgical waste slags were heated from room temperature to 1300°C, the weight loss of Blast Furnace (BF) slag and ladle furnace (LF) refining slag are only 2.25% and 0.9%, respectively, while the weight loss of Basic Oxygen Furnace (BOF) slag and electric arc furnace (EAF) slag are more than 5%. These metallurgical waste slags have a good absorption capacity for the microwave irradiation, the absorption capacity of microwave decreases in the order of converter slag > EAF carbon steel slag > baste furnace slag. In addition, the temperature-rising rates of the metallurgical waste slags increase with the microwave power and the quality or the particle sizes of slags. Furthermore, the crystalline phases of treated slag with microwave are similar with that of the untreated metallurgical slag. A number of internal cracks in particles of metallurgical slag can be found or extended after microwave treatment.
Computational Wear and Contact Modeling for Fretting Analysis with Isogeometric Dual Mortar Methods
Authors: Farah Philipp , Gitterle Markus , Wall Wolfgang A. , Popp Alexander
Published: February 2016

A finite element framework based on dual mortar methods is presented for simulating fretting wear effects in the finite deformation regime. The mortar finite element discretization is realized with Lagrangean shape functions as well as isogeometric elements based on non-uniform rational B-splines (NURBS) in two and three dimensions. Fretting wear effects are modeled in an incremental scheme with the help of Archard’s law and the worn material is considered as additional contribution to the gap function. Numerical examples demonstrate the robustness and accuracy of the presented algorithm.