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Rietveld refinement and optical properties of SrWO_4:eu^(3+) powders prepared by the non-hydrolytic sol-gel method

Journal of Rare earths 2015年第2期33卷 113-128页

作者： P.F.S.Pereira I.C.Nogueira e.longo e.J.Nassar I.l.V.Rosa l.S.Cavalcante Chemistry Institute University of the State of Sao Paulo Julio de Mesquita Filho-UNESP Francisco DegniAraraquara-SP 14800-900 Brazil l.e.-Chemistry Department Federal University of Sao Carlos Via Washington Luis Km 235Sao Carlos-SP 13565-905 Brazil University of Franca-UNIFRAN Via Dr.Armando Sales de OliveiraNo.201 Franca-SP 14404-600 Brazil CCN-DQ-GeRATeC University of the State of Piauí Joao Cabral 2231 P.O.Box 391Terezina PI 64002-150 Brazil

We investigated the effect of annealing time on the structure and optical properties of Sr WO4：eu^3＋ powders prepared by the non-hydrolytic sol-gel method and heat treated at 800 ℃ for 2,4,8 and 16 *** and differential thermal analyses revealed that Sr WO4：eu^3＋ powders were obtained at about 800 ℃.X-ray diffraction patterns and Rietveld refinement data confirmed that all powders had a scheelite-type tetragonal ***-Raman and Fourier transform infrared spectra indicated structural order at short range and anti-symmetric stretching vibrations of O-W-O bonds associated with tetrahedral[WO4]*** properties were investigated by ultraviolet-visible（UV-vis）diffuse reflectance,and photoluminescence（Pl）data which provided the evolution of quantum efficiency（η）and lifetime（τ）.UV-vis spectroscopy evidenced intermediate energy levels within the band gap of Sr WO4：eu^3＋ *** properties validated that the eu^3＋ electric-dipole（^5D0→^7F2）transition in Pl.e.ission spectra was dominant which proved that eu^3＋ ions were positioned in a site without an inversion center.[（^5D0→^7F2）/（^5D0→^7F1）]band ratios showed that eu^3＋ ions were located in a low symmetry *** Pl.e.ission,ηandτproved the dependence on the annealing time in the behavior of Sr WO4：eu3＋powders with a higher relative emission Pl intensity as well as higherηandτval.e. related to other samples when heat treated at 800℃ for 8 h.

关键词： SrWO4 Rietveld refinement optical band gap eu^(3+) +-rare earth luminescence

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Kinetics of the Oxidative Dehydrogenation of Propane over a VMgO Catalyst

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Journal of Natural Gas Chemistry 2002年第1期11卷 33-42页

作者： l.late e.A.Blekkan DepartmentofChemicalegineering NorwegianUniversityofScienceandTechnology（NTNU）N－7491TrondheimNorway DepartmentofChemicalegineering NorwegianUniversityofScienceandTechnology（NTNU）N－7491TrondheimNor

The reaction kinetics of the oxidative dehydrogenation of propane was studied at 475-550°C over a VMgO catalyst. Vanadium-magnesium-oxides are among the most selective and active catalysts for the dehydrogenation of propane to propylene. Selectivity to propylene up to about 60% was obtained at 10% conversion, but the selectivity decreased with increasing conversion. No oxygenates were detected, the only by-products were CO and CO2. The reaction rate of propane was found to be first order in propane and close to zero order in oxygen, which is in agreement with a Mars van Krevelen mechanism with the activation of the hydrocarbon as the rate determining step. The activation energy of the conversion of propane was found to be 122±6 kJ/mol.

关键词： propane oxidative dehydrogenation VMgO kinetics

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Two Cyclic Peptides Produced by the endophytic Fungus # 2221 from Castaniopsis fissa on the South China Sea Coast

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Chinese Chemical letters 2005年第2期16卷 219-222页

作者： WenQingYIN JieMingZOU ZhiGangSHe l.l.P.Vrijmoed e.B.GarethJones YongChenglIN DepartmentofA_ppl.e.Chemistry ZhongshanUniversityGuangzhou510275 DepartmentofAppl.e.Chemistry ZhongshanUniversityGuangzhou510275／／GuilinSanjinPharmaceuticalCo.Ltd.Guilin541004／／DepartmentofchemistryandchemicalengineeringGuangxiNormalUniversityGuilin5411004 GuilinSanjinPharmaceuticalCo.ltd. Guilin541004 DepartmentofBiologyandChemistry CityUniversityofHongKongHongKong

New cyclic peptides 1 and 2 were isolated from the endophytic fungus #2221 fromCastaniopsis fissa on the south China sea coast. By 2D NMR methods and chiral HPlC technique,their structures were elucidated as cyclo (l-... 详细信息

关键词： endophytic fungus cyclic peptides metabolite.

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硅酸钙对水稻稻瘟病和胡麻斑病病害强度及水稻产量的影响

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国外农学（植物保护） 1992年第3期5卷 9-11页

作者： Datnoff l.e. 胡广淦

在佛罗里达州,水稻主要种植在亚热带气候下的有机土壤中.这种土壤富含有机质而植物可利用硅(Si)含量低.1987和1988年分别用硅酸钙炉渣按0、5、10和15Mg/公顷用量撒施.1987年,使用硅酸钙炉渣后,稻瘟病比对照减少30.5%,胡麻斑病减少15.0%.... 详细信息

在佛罗里达州,水稻主要种植在亚热带气候下的有机土壤中.这种土壤富含有机质而植物可利用硅(Si)含量低.1987和1988年分别用硅酸钙炉渣按0、5、10和15Mg/公顷用量撒施.1987年,使用硅酸钙炉渣后,稻瘟病比对照减少30.5%,胡麻斑病减少15.0%.1988年,稻瘟病和胡麻斑病分别比对照减少17.4%和32.4%.硅渣-病情和硅渣-产量关系可用线性方程和二次方程分别描述。且相关显著(P<0.05).在水稻秸秆样本中,只有硅(Si)含量随着硅渣使用量增加,而比对照显著增加(P<0.05)。钙(Ca)则不表现明显增加.本研究结果表明硅含量是病害强度降低的原因.

关键词：水稻硅酸钙稻瘟病产量胡麻斑病

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Optimizing outcomes for patients with gastric cancer peritoneal carcinomatosis

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World Journal of Gastrointestinal Oncology 2018年第10期10卷 282-289页

作者： Jennifer l leiting Travis e Grotz Division of Hepatobiliary and Pancreas Surgery Mayo Clinic

Peritoneal carcinomatosis (PC) from gastric cancer has traditionally been considered a terminal progression of the disease and is associated with poor survival out-comes. Positive peritoneal cytology similarly worsens the survival of patients with gastric cancer and treatment options for these patients have been limited. Recent ad-vances in multimodality treatment regimens have led to innovative ways to care for and treat patients with this disease burden. One of these advances has been to use neoadjuvant therapy to try and convert patients with positivecytologyorlow-volume PC to negative cytolo-gy with no evidence of active peritoneal *** strategies include the use of neoadjuvant systemic chemotherapy alone,using neoadjuvant laparoscopic heated intraper itoneal chemotherapy(NlHIPeC)after systemic chemotherapy,or using neoadjuvant intra-peritoneal and systemic chemother apy(NIPS)in a bi-dir ectional manner. For patients with higher volume PC,cytoreductive surgery (CRS) and hyperthermic intrape-ritoneal chemotherapy(HIPeC)have been mainstays of treatment. When used together, CRS and HIPeC can improve overall outcomes in properly selected patients,but overall survival outcomes remain unacceptably *** extent of peritoneal disease, commonly measured by the peritoneal carcinomatosis index (PCI), and the com-pleteness of cytor eduction,has been shown to greatly impact outcomes in patients undergoing CRS and *** uses of NlHIPeC and NlHIPeC plus NIPS have both been shown to decrease the PCI and thus increase the opportunity for complete cytoreduction. Newer therapies like pressurized intraperitoneal aerosol chemother apy and immunotherapy, such as catumaxomab, along with improved systemic chemotherapeutic regimens, are being explored with great *** is exciting progress being made in the management of PC from gastric can-cer and its’ treatment is no longer futile.

关键词： Peritoneal carcinomatosis index Peritoneal carcinomatosis Gastric cancer Cytoreductive surgery Heated intraperitoneal chemotherapy Neoadjuvant intraperitoneal and systemic chemotherapy

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创造性地降低成本

创造性地降低成本

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作者： l.e.·泰格里弗瑞(l.e. Tagliaferri)

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Digital twin intelligent system for industrial internet of things-based big data management and analysis in cloud environments

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Virtual Reality & Intelligent Hardware 2022年第4期4卷 279-291页

作者： Christos l.STeRGIOU Kostas e.PSANNIS Department of Appl.e. Informatics University of MacedoniaGreece

This work surveys and illustrates multiple open chal.e.ges in the field of industrial Internet of Things(IoT)-based big data management and analysis in cloud *** arising from the fields of machine learning in cloud infrastructures,artificial intelligence techniques for big data analytics in cloud environments,and federated learning cloud systems are ***,reinforcement learning,which is a novel technique that allows large cloud-based data centers,to allocate more energy-efficient resources is ***,we propose an architecture that attempts to combine the features offered by several cloud providers to achieve an energy-efficient industrial IoT-based big data management framework(eeIBDM)established outside of every user in the *** data can be integrated with techniques such as reinforcement and federated learning to achieve a digital twin scenario for the virtual representation of industrial IoT-based big data of machines and room ***,we propose an algorithm for determining the energy consumption of the infrastructure by evaluating the eeIBDM ***,future directions for the expansion of this research are discussed.

关键词： Machine learning IoT Big data Cloud computing Management Analytics Digital twin Scenario energy efficiency

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Quantum-dot microlasers based on whispering gal.e.y mode resonators

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light(Science & Applications) 2021年第5期10卷 785-795页

作者： A.e.Zhukov N.V.Kryzhanovskaya e.l.Moiseev M.V.Maximov laboratory of quantum optoelectronics National Research University Higher School of EconomicsKantemirovskaya 3ASt.Petersburg 194100Russia Nanophotonics laboratory Alferov UniversityKhlopina 8/3St.Petersburg 194021Russia

The subject of this paper is microlasers with the emission spectra determined by the whispering gal.e.y *** to the total internal reflection of light on the sidewalls,a high Q-factor is achieved until the diameter is comparable to the *** light emission predominantly occurs in the plane of the structure,which facilitates the microlaser integration with other *** focus on microdisk lasers with various types of the In(Ga)As quantum dots(QDs).Deep localization of charge carriers in spatilly separated regions suppresses the lateral diffusion and makes it possible to overcome the undesirable effect of non-adiative recombination in deep ***,using conventional.e.itaxial structures and relatively simple post-growth processing methods,it is possible to realize small microlasers capable of operating without temperature stabilization at elevated *** low sensitivity of QDs to epitaxial and manufacturing defects allows fabricating microlasers using IIV heterostructures grown on silicon.

关键词： Quantum mode overcome

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A new currency for mutualism?Fungal.e.dophytes al.e. antioxidant activity in hosts responding to drought

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Fungal Diversity 2012年第3期54卷 39-49页

作者： Cyd e.Hamilton Taryn l.Bauerle MTT Agrifood and Biotech Plant Production UnitJokioinenFinland Cornell University HorticultureIthacaNYUSA

Fungal.e.dophytes have significant effects on host performance including but not limited to changes in reproductive output,as well as,biotic and abiotic stress *** ultimate mechanisms for resistance to herbivory have been documented in a number of fungal-plant symbiota and invol.e.the production of alkaloids by the *** have thus been defined as a currency responsible for increased host resistance to *** provide support for the hypothesis that another currency may be responsible for increased host tolerance to abiotic stress resulting from endophyte colonization;namely *** report comparatively higher activity of antioxidants in endophyte colonized hosts resulting from abiotic stress and propose antioxidants are another currency via which mutualistic interactions between fungal.e.dophytes and their hosts can *** recognize fungal.e.dophyte interactions are diverse and complex and include antagonisms,commensalisms,and mutualisms.

关键词： Symbiont Stress epichloe Neotyphodium Stress tolerance Reactive oxygen species

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Tuning thermal.e.pansion by a continuing atomic rearrangement mechanism in a multifunctional titanium alloy

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Journal of Materials Science & Technology 2021年第21期80卷 234-243页

作者： D.l.Gong H.l.Wang e.G.Obbard S.J.li R.Yang Y.l.Hao Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and engineering University of Science and Technology of ChinaShenyang110016China School of Mechanical.e.gineering Dongguan University of TechnologyDongguan523808China Department of electrical.e.gineering and Telecommunications University of New South WalesSydneyNSW2052Australia

As to multifunctional titanium alloys with high strength and low elastic modulus, thermal training is crucial to tune their thermal.e.pansion from positive to negative, resulting in a novel linear expansion which is stable in a wide temperature range. Aided by the high-order Hooke's law of elastic solids,a reversible atomic rearrangement mechanism was proposed to explain the novel findings which are unexpected from typical shape memory alloys. To confirm this continuous mechanism, a Ti-Nb based alloy, which possesses a nanoscale spongy microstructure consisting of the interpenetrated Nb-rich and Nb-lean domains produced by spinodal decomposition, was used to trace the crystal structure change by in-situ high energy synchrotron X-ray diffraction analyses. By increasing exposure time, the overlapped diffraction peaks can be separated accurately. The calculated results demonstrate that, in the nanoscale Nb-lean domains, the crystal structure parameters vary linearly with changing temperature along the atomic pathway of the bcc-hcp transition. This linear relationship in a wide temperature range is unusual for first-order martensitic shape memory alloys but is common for Invar alloys with high-order spin transitions. Furthermore, the alloy exhibits smooth DSC curves free of transformation-induced heat peaks observed in shape memory alloys, which is consistent with the proposed mechanism that the reversible transition is of high-order.

关键词： Coefficient of thermal.e.pansion Multifunctional titanium alloys Spongy microstructure Atomic rearrangement elastic anisotropy

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