Synthesis and Characterization of WC-Co Nanosized Composite Powders With in situ Carbon and Gas Carbon Sources

Qiumin Yang,Jiangao Yang,Hailin Yang,Wei Su,Jianming Ruan 대한금속·재료학회 2016 METALS AND MATERIALS International Vol.22 No.4

This study presented nanosized WC-Co composite powders synthesized using a one-step reduction-carbonization process with a combination of CH4/H2 as a gas carbon source and soluble starch as an in situ carbon source. The results of carbon analysis and X-ray diffraction revealed that WC-Co nanocomposite powders with a pure WC and Co phase could be obtained at 1100 °C after 0.5 h. A higher gas flow ratio of CH4/H2 during the reduction-carbonization process led to a higher total carbon content of the sample. A field emission scanning electron microscope confirmed that the particles in the WC-6 wt% Co composite powders had the lowest average size of 43 nm with equiaxed shapes. A sintering neck was observed in the WC-3 wt% Co composite powders whereas faceted particles were found in the WC-12 wt% Co composite powders. Moreover, this method has advantages of simple processing, rapid synthesis and good applicability in potential industry application.

Research on Spider Fine-Grained Recognition Technology Based on Transfer Learning

Jianming Wang,Longfeng Deng,Chenyang Shi,Guosheng Ye,Zizhong Yang 한국정보과학회 2023 Journal of Computing Science and Engineering Vol.17 No.4

Few-shot image recognition represents a critical challenge in computer vision research. The scarcity of samples often results in inaccurate classification, limited generalization capabilities, and overfitted model recognition. To address these issues, the present study focuses on spider image recognition utilizing transfer learning and data augmentation techniques in limited sample settings. First, the BasNet image segmentation model and background replacement algorithm are used to extract species image data from the foreground; data augmentation is then applied to address the scarcity of samples. Second, a layer-by-layer fine-tuned transfer learning strategy based on the ResNet-50 model is devised. Specifically, to mitigate overfitting in the few-shot image classification task, the first two residual blocks are frozen so that only the last two are trained. To enhance the model’s representation and generalization abilities, the SSC-ResNet-50 optimization model is constructed by introducing symmetry techniques. This study aims to enhance the accuracy and performance of spider image recognition. The experimental results demonstrate that the improved SSC-ResNet-50 model achieves an average accuracy of 99.1% in recognizing five types of spiders, thereby surpassing the performance of traditional models. These findings offer valuable insights for the field of small-sample high-precision image recognition.

Optimized Ciphertext-Policy Attribute-Based Encryption with Efficient Revocation

Yang Li,Jianming Zhu,Xiuli Wang,Yanmei Chai,Shuai Shao 보안공학연구지원센터 2013 International Journal of Security and Its Applicat Vol.7 No.6

운율 이론 및 구조 운율 분석

陸儉明(Jianming Lu),沈陽(Yang Shen),尹愛庚(번역자) 중국어문논역학회 2021 中國語文論譯叢刊 Vol.- No.48

운율 형식은 어법 의미를 ‘발현’시키고 동시에 어법 구조에 ‘제약’을 가하는 작용을 한다. 운율 이론은 운율 형태론과 운율 통사론이라는 두 가지 방면을 포함한다. 운율형태론에 관련된 운율학의 원리에는 ‘상대적 강세 원칙’과 ‘음보 이분 원칙’, ‘음보 단핵 법칙’ 등이 있다. 운율 통사론에 관련된 운율학의 원리에는 ‘핵 강세 할당 규칙’과 ‘2분지 강세 규칙’ 등이 있다. 하지만 이러한 운율 규칙들 사이에는 충돌이 발생할 수도 있다. 이때 운율 충돌을 조정하는 방법에는 몇 가지가 있다. 기존의 운율 규칙을 수정하여 재해석할 수도 있고 운율 규칙의 ‘제재’를 구조적으로 피할 수도 있다. The prosody form ‘expresses’ the grammatical meaning, and at the same time adds a “restriction” on the grammatical structure. Prosody theory includes two aspects: prosody morphology and prosody syntax. The principles of prosody related to prosody morphology include the ‘relative prominence principle’, the ‘foot dichotomy principle’, and the ‘foot mononuclear principle’. The principles of prosody related to prosody syntax include the ‘nuclear stress assignment rule’ and the ‘binary stress rule’. However, prosodic conflicts may arise between these prosody rules. There are several ways to adjust the prosodic conflict at this time. In order to adjust the prosodic conflict, the existing prosody rules can be reinterpreted by modifying them, or the ‘sanctions’ of the prosody rules can be structurally avoided.

Reynolds and froude number effect on the flow past an interface-piercing circular cylinder

구본국,Jianming Yang,연성모,Frederick Stern 대한조선학회 2014 International Journal of Naval Architecture and Oc Vol.6 No.3

The two-phase turbulent flow past an interface-piercing circular cylinder is studied using a high-fidelity orthogonal curvilinear grid solver with a Lagrangian dynamic subgrid-scale model for large-eddy simulation and a coupled level set and volume of fluid method for air-water interface tracking. The simulations cover the sub-critical and critical and post critical regimes of the Reynolds and sub and super-critical Froude numbers in order to investigate the effect of both dimensionless parameters on the flow. Significant changes in flow features near the air-water interface were observed as the Reynolds number was increased from the sub-critical to the critical regime. The interface makes the separation point near the interface much delayed for all Reynolds numbers. The separation region at intermediate depths is remarkably reduced for the critical Reynolds number regime. The deep flow resembles the single-phase tur-bulent flow past a circular cylinder, but includes the effect of the free-surface and the limited span length for sub-criti-cal Reynolds numbers. At different Froude numbers, the air-water interface exhibits significantly changed structures, including breaking bow waves with splashes and bubbles at high Froude numbers. Instantaneous and mean flow fea-tures such as interface structures, vortex shedding, Reynolds stresses, and vorticity transport are also analyzed. The results are compared with reference experimental data available in the literature. The deep flow is also compared with the single-phase turbulent flow past a circular cylinder in the similar ranges of Reynolds numbers. Discussion is pro-vided concerning the limitations of the current simulations and available experimental data along with future research.

Free in-plane vibration of thin-walled rings with elastic supports

Mohammadjavad Abedinilaksar,Jianming Yang 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.1

The free in-plane vibration of a thin-walled ring with elastic supports is investigated in this work. These supports are represented as linear springs in radial, tangential, and torsional directions to mimic bolt supports in the real world. With the Euler-Bernoulli theory and the assumption of inextensibility, the natural frequency and mode shape are obtained. Finally, the effects of model parameters such as radius-to-thickness ratio and support stiffness are studied. The model is verified by comparing results against available publications on simpler boundary conditions.

Reynolds and froude number effect on the flow past an interface-piercing circular cylinder

Koo, Bonguk,Yang, Jianming,Yeon, Seong Mo,Stern, Frederick The Society of Naval Architects of Korea 2014 International Journal of Naval Architecture and Oc Vol.6 No.3

The two-phase turbulent flow past an interface-piercing circular cylinder is studied using a high-fidelity orthogonal curvilinear grid solver with a Lagrangian dynamic subgrid-scale model for large-eddy simulation and a coupled level set and volume of fluid method for air-water interface tracking. The simulations cover the sub-critical and critical and post critical regimes of the Reynolds and sub and super-critical Froude numbers in order to investigate the effect of both dimensionless parameters on the flow. Significant changes in flow features near the air-water interface were observed as the Reynolds number was increased from the sub-critical to the critical regime. The interface makes the separation point near the interface much delayed for all Reynolds numbers. The separation region at intermediate depths is remarkably reduced for the critical Reynolds number regime. The deep flow resembles the single-phase turbulent flow past a circular cylinder, but includes the effect of the free-surface and the limited span length for sub-critical Reynolds numbers. At different Froude numbers, the air-water interface exhibits significantly changed structures, including breaking bow waves with splashes and bubbles at high Froude numbers. Instantaneous and mean flow features such as interface structures, vortex shedding, Reynolds stresses, and vorticity transport are also analyzed. The results are compared with reference experimental data available in the literature. The deep flow is also compared with the single-phase turbulent flow past a circular cylinder in the similar ranges of Reynolds numbers. Discussion is provided concerning the limitations of the current simulations and available experimental data along with future research.

Solidification/stabilization of simulated cadmium-contaminated wastes with magnesium potassium phosphate cement

Ying Su,Jianming Yang,Debin Liu,Shucong Zhen,Naixi Lin,Yongxin Zhou 대한환경공학회 2016 Environmental Engineering Research Vol.21 No.1

Magnesium potassium phosphate cement (MKPC) is an effective agent for solidification/stabilization (S/S) technology. To further explore the mechanism of the S/S by MKPC, two kinds of Cd including Cd(NO₃)2 solution (L-Cd) and municipal solid waste incineration fly ash (MSWI FA) adsorbed Cd (S-Cd), were used to compare the effects of the form of heavy metal on S/S. The results showed that all the MKPC pastes had a high unconfined compressive strength (UCS) above 11 MPa. For L-Cd pastes, Cd leaching concentration increased with the increase of Cd content, and decreased with the increase of curing time. With the percentage of MSWI FA below 20%, S-Cd pastes exhibited similar Cd leaching concentrations as those of L-Cd pastes, while when the content of MSWI FA come up to 30%, the Cd leaching concentration increased significantly. To meet the standard GB5085.3-2007, the highest addition of S-Cd was 30% MSWI FA (6% Cd contained), with the Cd leaching concentration of 0.817 mg/L. The S/S of L-Cd is mainly due to chemical fixation, and the hydration compound of Cd was NaCdPO₄, while the S/S of S-Cd is due to physical encapsulation, which is dependent on the pore/crack size and porosity of the MKPC pastes.

Characterization and mapping of a Prbs gene controlling spike development in Hordeum vulgare L.

Yi Shang,Jianming Yang,Jinghuan Zhu,Wei Hua,Junmei Wang,Qiaojun Jia 한국유전학회 2014 Genes & Genomics Vol.36 No.3

The barley mutant, poly-row-and-branchedspike (prbs) showed altered inflorescence morphology:complete conversion of the rudimentary lateral spikelets intwo-rowed barley into fully developed fertile spikeletssimilar to the six-rowed phenotype, and additional spikeletsin the middle of spike. Moreover, branched spikes emergedin progeny from a cross between the mutant and a sixrowedbarley cultivar. Morphological observation of thedevelopment of immature spikes of the mutant anddescendants with branched spikes showed that the Prbsgene is involved in spikelet development in the triplemoundstage. In mutant prbs, new meristems initiated atthe flanks of lateral spikelets and middle spikelet meristemswere converted to branch meristems, developing branchedspikes. These observations suggested that the Prbs geneplays a crucial role in spikelet initiation and identitymaintenance. The Prbs gene may be an important modifierin inflorescence differentiation from a panicle into a spike. The branched spikes emerging in hybrids from a crossbetween the mutant and six-rowed barley cultivar were notconferred by the gene vrs1 or Int-c, which decide spikemorphology in six-rowed barley. These results imply thatalthough six-row genes vrs1 and Int-c and prbs have similareffects on lateral spikelet development, they have differentfunctions in branched spikes. The Prbs gene wasmapped to chromosome 3H between SSR markerBmag0023 and marker Cbic60 at a genetic distance of 3.3and 5.4 centimorgans (cM), respectively.

Purification process and reduction of heavy metals from industrial wastewater via synthesized nanoparticle for water supply in swimming/water sport

Leiming Fu,Junlong Li,Jianming Yang,Yutao Liu,Chunxia He,Yifei Chen Techno-Press 2023 Advances in nano research Vol.15 No.5

Heavy metals, widely present in the environment, have become significant pollutants due to their excessive use in industries and technology. Their non-degradable nature poses a persistent environmental problem, leading to potential acute or chronic poisoning from prolonged exposure. Recent research has focused on separating heavy metals, particularly from industrial and mining sources. Industries such as metal plating, mining operations, tanning, wood and chipboard production, industrial paint and textile manufacturing, as well as oil refining, are major contributors of heavy metals in water sources. Therefore, removing heavy metals from water is crucial, especially for safe water supply in swimming and water sports. Iron oxide nanoparticles have proven to be highly effective adsorbents for water contaminants, and efforts have been made to enhance their efficiency and absorption capabilities through surface modifications. Nanoparticles synthesized using plant extracts can effectively bind with heavy metal ions by modifying the nanoparticle surface with plant components, thereby increasing the efficiency of heavy metal removal. This study focuses on removing lead from industrial wastewater using environmentally friendly, cost-effective iron nanoparticles synthesized with Genovese basil extract. The synthesis of nanoparticles is confirmed through analysis using Transmission Electron Microscope (TEM) and X-ray diffraction, validating their spherical shape and nanometer-scale dimensions. The method used in this study has a low detection limit of 0.031 ppm for measuring lead concentration, making it suitable for ensuring water safety in swimming and water sports.