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Frontiers of Chemical Science and Engineering 2012年第4期6卷 371-380页

作者： Diah Susanti stefanus haryo n Hasnan nisfu Eko Prasetio nugroho Hariyati Purwaningsih GeorgeEndri Kusuma Shao-Ju Shih Materials and Metallurgical Engineering Department Faculty of Industrial Technology Sepuluh Nopember Institute of Technology (ITS) Surabaya 60111 Indonesia Mechanical Engineering Department Surabaya State Shipbuilding Polytechnic Surabaya 60111 Indonesia Materials Science and Engineering Department Taiwan Tech (NTUST) Taipei 106 China

Tungsten （VI） oxide （WO3） nanomaterials were synthesized by a sol-gel method using WC16 and C2HsOH as precursors followed by calcination or hydrothermal treatment. X-Ray diffraction （XRD）, scanning electron microscopy （SEM） and high resolution transmission electron microscopy （HRTEM） equipped with energy dispersive X-ray spectroscopy （EDX） were used to characterize the structure and morphology of the materials. There were significant differences between the WO3 materials that were calcinated and those that were subjected to a hydrothermal process. The XRD results revealed that calcination temperatures of 300℃and 400℃ gave hexagonal structures and temperatures of 500℃ and 600℃ gave monoclinic structures. The SEM images showed that an increase in calcination temperature led to a decrease in the WO3 powder particle size. The TEM analysis showed that several nanoparticles agglomerated to form bigger clusters. The hydrothermal process produced hexagonal structures for holding times of 12, 16, and 20 h and monoclinic structures for a holding time of 24 h. The SEM results showed transparent rectangular panicles which according to the TEM results originated from the aggregation of several nanotubes.

关键词： WO3 nanomaterial sol-gel method calcina-tion hydrothermal

Plasmodium falciparum found in the bone marrow of a child in Manado City,East Indonesia:A case report

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Asian Pacific Journal of Tropical Medicine 2017年第10期10卷 1015-1017页

作者： Suryadi n.n.Tatura stefanus Gunawan Janno Bernadus Sianne Sandjoto Indonesian national Expert Committee of Malaria Ministry of Health Republic of IndonesiaIndonesia Division of Pediatric Infection and Tropical Medicine Department of PediatricFaculty of MedicineSam Ratulangi UniversityManadoIndonesia Division of Pediatric Infection and Tropical Medicine Department of PediatricProf.R.D.Kandou General HospitalManadoIndonesia Estella Pediatric Cancer Center Prof.Dr.R.D.Kandou General HospitalManadoIndonesia Division of Hematology Oncology Department of PediatricFaculty of MedicineSam Ratulangi UniversityManadoIndonesia Department of Parasitology Faculty of MedicineSam Ratulangi UniversityManadoIndonesia Department of Pediatric Faculty of MedicineSam Ratulangi UniversityManadoIndonesia

In Indonesia, there are at least 1.3 million cases of malaria each year and Plasmodium falciparum appears to be the most common *** finding of Plasmodium is important for the diagnosis and management of *** is a case of a 4-year-and-9-month-old male who lived in Manado, East *** presented with a prolonged fever, was pale in appearance, and was easily fatigued over the last 3 *** was found on the initial physical *** laboratory findings found pancytopenia and severe *** he was referred to our hospital, at the primary health center, the initial work-up was negative for Plasmodium with the serial Rapid Diagnostic Test and microscopic peripheral blood *** there were signs and symptoms mimicking malignancy, the patient was referred to our hospital for further malignancy work-up.A bone marrow puncture was done and we incidentally found Plasmodium falciparum in a microscopic bone marrow *** was a rare case because Plasmodium was not initially found in the preliminary work-up(Rapid Diagnostic Test and Microscopic) and qPCR is not a routine work-up for Plasmodium suspected *** the mortality rate of malaria is high, this condition can be treated if the clinician was aware of the clinical signs and symptoms in the early onset and prompt medical treatment is *** a severe case with an unclear etiology of fever and with signs and symptoms mimicking malignancy, qPCR is ***, a bone marrow puncture can also be considered to exclude the possibility of a malaria infection.

关键词： Malaria Plasmodium falciparum Peripheral blood Bone marrow

In-situ observation of twinning and detwinning in AZ31 alloy

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Journal of Magnesium and Alloys 2022年第12期10卷 3418-3432页

作者： Wu Gong Ruixiao Zheng stefanus Harjo Takuro Kawasaki Kazuya Aizawa nobuhiro Tsuji J-PARC Center Japan Atomic Energy Agency2-4 Shirane ShirakataTokaiNakaIbaraki 319-1195Japan Center for Elements Strategy Initiative for Structural Materials Kyoto UniversityYoshidahonmachiSakyo-kuKyoto 606-8501Japan Department of Materials Science and Engineering Kyoto UniversityYoshida-honmachiSakyo-kuKyoto 606-8501Japan School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Twinning and detwinning behavior of a commercial AZ31 magnesium alloy during cyclic compression–tension deformation with a total strain amplitude of 4%(±2%) was evaluated using the complementary techniques of in-situ neutron diffraction, identical area electron backscatter diffraction, and transmission electron microscopy. In-situ neutron diffraction demonstrates that the compressive deformation was dominated by twin nucleation, twin growth, and basal slip, while detwinning dominated the unloading of compressive stresses and subsequent tension stage. With increasing number of cycles from one to eight: the volume fraction of twins at-2% strain gradually increased from 26.3% to 43.5%;the residual twins were present after 2% tension stage and their volume fraction increased from zero to 3.7% as well as a significant increase in their number;and the twinning spread from coarse grains to fine grains involving more grains for twinning. The increase in volume fraction and number of residual twins led to a transition from twin nucleation to twin growth, resulting in a decrease in yield strength of compression deformation with increasing cycles. A large number of-component dislocations observed in twins and the detwinned regions were attributed to the dislocation transmutation during the twinning and detwinning. The accumulation of barriers including twin boundaries and various types of dislocations enhanced the interactions of migrating twin boundary with these barriers during twinning and detwinning, which is considered to be the origin for increasing the work hardening rate in cyclic deformation of the AZ31 alloy.

关键词： Magnesium neutron diffraction Twinning Detwinning Dislocation transmutation

Strengthening of high-entropy alloys via modulation of cryo-pre-straining-induced defects

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Journal of Materials Science & Technology 2022年第34期129卷 251-260页

作者： Daixiu Wei Wu Gong Liqiang Wang Bowen Tang Takuro Kawasaki stefanus Harjo Hidemi Kato Institute for Materials Research Tohoku University2-1-1 KatahiraSendaiMiyagi 980-8577Japan J-PARC Center Japan Atomic Energy Agency2-4ShirakataTokaiNaka-gunIbaraki 319-1195Japan State Key Laboratory of Metal Matrix Composites School of Material Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Graduate School of Materials Science Tohoku University6-6Aramaki Aza AobaAoba-kuSendaiMiyagi 980-8579Japan

Owing to their attractive structure and mechanical properties,high-entropy alloys(HEAs) and mediumentropy alloys(MEAs) have attracted considerable research *** strength of HEAs/MEAs with a single face-centered cubic(FCC) phase,on the other hand,requires ***,in this study,we demonstrate a strategy for increasing the room-temperature strength of FCC-phase HEAs/MEAs by tuning cryo-pre-straining-induced crystal defects via the temperature-dependent stacking fault energyregulated plasticity *** neutron diffraction line profile analysis and electron microscope observation,the effect of the tuned defects on the tensile strength was *** to the cryorolling-induced high dislocation density,mechanical twins,and stacking faults,the room-temperature yield strength of an equiatomic CoCrFeni HEA was increased by ~290%,from 243 MPa(as-recrystallized)to 941.6 MPa(30% cryo-rolled),while maintaining a tensile elongation of 18%.After partial recovery via heat treatment,the yield strength and ultimate tensile strength decreased slightly to 869 and 936 MPa,***,the elongation increased to 25.6%,The dislocation density and distribution of the dislocations were found to contribute to the strengthening caused by forest dislocations,which warrants further *** study discussed the possibility of developing single-phase high-performance HEAs by tuning pre-straining-induced crystal defects.

关键词： High-entropy alloys Cryo-pre-straining Crystal defects neutron diffraction Mechanical property

A Cross Entropy-Genetic Algorithm for m-Machines no-Wait Job-ShopScheduling Problem

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Journal of Intelligent Learning Systems and Applications 2011年第3期3卷 171-180页

作者： Budi Santosa Muhammad Arif Budiman stefanus Eko Wiratno 不详

no-wait job-shop scheduling (nWJSS) problem is one of the classical scheduling problems that exist on many kinds of industry with no-wait constraint, such as metal working, plastic, chemical, and food industries. Several methods have been proposed to solve this problem, both exact (i.e. integer programming) and metaheuristic methods. Cross entropy (CE), as a new metaheuristic, can be an alternative method to solve nWJSS problem. This method has been used in combinatorial optimization, as well as multi-external optimization and rare-event simulation. On these problems, CE implementation results an optimal value with less computational time in average. However, using original CE to solve large scale nWJSS requires high computational time. Considering this shortcoming, this paper proposed a hybrid of cross entropy with genetic algorithm (GA), called CEGA, on m-machines nWJSS. The results are compared with other metaheuritics: Genetic Algorithm-Simulated Annealing (GASA) and hybrid tabu search. The results showed that CEGA providing better or at least equal makespans in comparison with the other two methods.

关键词： no-Wait Job Shop Scheduling Cross Entropy Genetic Algorithm Combinatorial Optimization

Definition of colorectal anastomotic leakage: A consensus survey among Dutch and Chinese colorectal surgeons

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World Journal of Gastroenterology 2017年第33期23卷 6172-6180页

作者： stefanus J van Rooijen Audrey CHM Jongen Zhou-qiao Wu Jia-fu Ji Gerrit D Slooter Rudi MH Roumen nicole D Bouvy Department of Surgery Máxima Medical Center nUTRIM School of nutrition and Translational Research in Metabolism Department of Surgery Maastricht University Medical Center Key laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Ward I of Gastrointestinal Cancer CenterPeking University Cancer Hospital and Institute

AIM To determine the level of consensus on the definition of colorectal anastomotic leakage(CAL) among Dutch and Chinese colorectal *** Dutch and Chinese colorectal surgeons were asked to partake in an online questionnaire. Consensus in the online questionnaire was defined as > 80% agreement between respondents on various statements regarding a general definition of CAL,and regarding clinical and radiological diagnosis of the *** Fifty-nine Dutch and 202 Chinese dedicated colorectal surgeons participated in the online survey. Consensus was found on only one of the proposed elements of a general definition of CAL in both countries: ‘extravasation of contrast medium after rectal enema on a CT scan'. Another two were found relevant according to Dutch surgeons: ‘necrosis of the anastomosis found during reoperation',and ‘a radiological collection treated with percutaneous drainage'. no consensus was found for all other proposed elements that may be included in a general *** There is no universally accepted definition of CAL in the netherlands and China. Diagnosis of CAL based on clinical manifestations remains a point of discussion in both countries. Dutch surgeons are more likely to report ‘subclinical' leaks as CAL,which partly explains the higher reported Dutch CAL rates.

关键词： Colorectal anastomotic leakage Colorectal surgery Definition Complication

Dust Suppression on Open Pit Drill Rigs--Case Study from Skorpion Zinc Mine

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Journal of Earth Science and Engineering 2015年第8期5卷 512-519页

作者： stefanus Andries Jakobus Potgieter Johannes Jacobus Labuschagne du Plessis Skorpion Zinc Mine Rosh Pinah Namibia Department of Mining Engineering Faculty of Engineering Build Environment and Information Technology University oJPretoria Pretoria 0028 South Africa

Spotters and samplers around the drill rigs can be exposed to high dust concentrations. In this study it was found that individuals were exposed to as much as 14.2 mg/m3, which exceeds the OEL （Occupational Exposure Level） of 10 mg/m3 [1]. The work on which this paper is based included an extensive literature study, as well as field investigations. number of additional dust suppression interventions was identified. These improvements, listed below, will assist in reducing dust concentrations arotmd the drill rigs： Increase maintenance frequency on the shroud, sealing ring, suction pipes and filters of the drill rigs. Design and install new overlapping rubber belts on the shroud of the DM45. Install an air-blocking shelf on the inside perimeter of the shroud of the DM45. Install an airflow meter to ensure that the Qc：QB ratio never drops below 3：1. Only allow wet drilling. Flush the dust collector system more regularly with compressed air to ensure that it does not become blocked. Introduce stricter supervision to ensure that the suction pipes are always connected to the shroud. Give drill rig operators more advanced training to ensure more effective drilling in order to reduce dust levels.

关键词： Dust suppression open pit mining drilling.