Influence of In-Plane Simple Shear Strain on the Grain Orientation Regulation and Stretch Formability of Pre-twinned AZ31 Magnesium Alloy Sheet

Liangliang Xue,Lifei Wang,Pengbin Lu,Qiang Zhang,Hua Zhang,Guangsheng Huang,Liwei Lu,Liuwei Zheng,Hanuma Reddy Tiyyagura,Hongxia Wang,Shuyong Jiang,Kwang Seon Shin 대한금속·재료학회 2023 METALS AND MATERIALS International Vol.29 No.10

Pre-twin is widely accepted as an efficient method for weakening the basal texture to improve the plasticity of magnesium alloys, particularly for formability. However, the enhancement is limited since the largest Schmid factor (SF) of basal slip cannot be achieved. In-plane simple shear strain is used to control the twin orientation in accordance with Schmid law to further decrease the basal texture and improve the formability of the Mg alloys sheet. Consequently, secondary regulation of initial twin orientation (SRITO) technology, a novel combination procedure, was developed. In this method, the AZ31 Mg alloys sheet is compressed to pre-twins with various volumes (1%, 3%, and 5%), then the twin orientation is regulated by in-plane simple shear strain for the second time. Compared with the as-received sample, the average fracture elongation of the annealed sample with the best properties improves from 15.3 to 28.8%, and the Erichsen value increases from 2.8 to 6.1 mm due to the regulation of twin orientation.

Confined 1D Propulsion of Metallodielectric Janus Micromotors on Microelectrodes under Alternating Current Electric Fields

Zhang, Liangliang,Xiao, Zuyao,Chen, Xi,Chen, Jingyuan,Wang, Wei American Chemical Society 2019 ACS NANO Vol.13 No.8

<P>There is mounting interest in synthetic microswimmers (“micromotors”) as microrobots as well as a model system for the study of active matters, and spatial navigation is critical for their success. Current navigational technologies mostly rely on magnetic steering or guiding with physical boundaries, yet limitations with these strategies are plenty. Inspired by an earlier work with magnetic domains on a garnet film as predefined tracks, we present an interdigitated microelectrodes (IDE) system where, upon the application of AC electric fields, metallodielectric (e.g., SiO<SUB>2</SUB>-Ti) Janus particles are hydrodynamically confined and electrokinetically propelled in one dimension along the electrode center lines with tunable speeds. In addition, comoving micromotors moved in single files, while those moving in opposite directions primarily reoriented and moved past each other. At high particle densities, turbulence-like aggregates formed as many-body interactions became complicated. Furthermore, a micromotor made U-turns when approaching an electrode closure, while it gradually slowed down at the electrode opening and was collected in large piles. Labyrinth patterns made of serpentine chains of Janus particles emerged by modifying the electrode configuration. Most of these observations can be qualitatively understood by a combination of electroosmotic flows pointing inward to the electrodes, and asymmetric electrical polarization of the Janus particles under an AC electric field. Emerging from these observations is a strategy that not only powers and confines micromotors on prefabricated tracks in a contactless, on-demand manner, but is also capable of concentrating active particles at predefined locations. These features could prove useful for designing tunable tracks that steer synthetic microrobots, as well as to enable the study of single file diffusion, active turbulence, and other collective behaviors of active matters.</P> [FIG OMISSION]</BR>

Novel Prognostic Nomograms for Hepatocellular Carcinoma Patients with Microvascular Invasion: Experience from a Single Center

Liangliang Xu,Lian Li,Peng Wang,Ming Zhang,Yanfang Zhang,Xiangyong Hao,Lvnan Yan,Bo Li,Tianfu Wen,Mingqing Xu 거트앤리버 소화기연관학회협의회 2019 Gut and Liver Vol.13 No.6

Background/Aims: Microvascular invasion (MVI) is an established risk factor for hepatocellular carcinoma (HCC). However, prediction models that specifically focus on the individual prognoses of HCC patients with MVI is lacking. Methods: A total of 385 HCC patients with MVI were randomly assigned to training and validation cohorts in a 2:1 ratio. The outcomes were disease-free survival (DFS) and overall survival (OS). Prognostic nomograms were established based on the results of multivariate analyses. The concordance index (C-index), calibration plots and Kaplan-Meier curves were employed to evaluate the accuracy, calibration and discriminatory ability of the models. Results: The independent risk factors for both DFS and OS included age, tumor size, tumor number, the presence of gross vascular invasion, and the presence of Glisson’s capsule invasion. The platelet-tolymphocyte ratio was another risk factor for OS. On the basis of these predictors, two nomograms for DFS and OS were constructed. The C-index values of the nomograms for DFS and OS were 0.712 (95% confidence interval [CI], 0.679 to 0.745; p<0.001) and 0.698 (95% CI, 0.657 to 0.739; p<0.001), respectively, in the training cohort and 0.704 (95% CI, 0.650 to 0.708; p<0.001) and 0.673 (95% CI, 0.607 to 0.739; p<0.001), respectively, in the validation cohort. The calibration curves showed optimal agreement between the predicted and observed survival rates. The Kaplan-Meier curves suggested that these two nomograms had satisfactory discriminatory abilities. Conclusions: These novel predictive models have satisfactory accuracy and discriminatory abilities in predicting the prognosis of HCC patients with MVI after hepatectomy.

Estimating Cement Compressive Strength from Microstructural Images Using Radial Basis Function Neural Networks

LiangLiang Zhang(장량량),Eun-Hu Kim(김은후),Sung-Kwun Oh(오성권) 대한전기학회 2019 대한전기학회 학술대회 논문집 Vol.2019 No.7

Structure of a permanent magnet motor used for electric vehicles to suppress the eddy current effect

Meiwei Zhang,Weili Li,Wanlu Xie,Liangliang Zhang 전력전자학회 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.9

A demagnetization fault in the permanent magnet (PM) may occur when the temperature exceeds the limit temperature of the PM material due to the limited heat dissipation of the rotor in PM motors in the driving system of electric vehicles. In addition, PM thermal stress arises as a result of the unbalanced axial temperature distribution of the motor. When the thermal stress exceeds the yield strength of PM, micro-deformation of the PM structure happens and affects the performance and structural reliability of the motor. In this study, the rotor structure of an 18 kW PM motor is improved, and an eddy current ring structure of stainless steel is proposed. First, the effects of eddy current rings with axial lengths of 2, 5, and 10 mm on the eddy current losses of PM are compared. Second, a three-dimensional, steady-state temperature model of the motor is established to analyze the effects of the eddy current rings with different axial lengths on rotor temperature when the motor is running at different speeds. Results show that the eddy current ring structure with 2 mm axial length has the best effect on reducing rotor temperature. Lastly, the simulation results are verified using the test results of the 18 kW PM motor.

Microfluidic fabrication of microparticles for biomedical applications

Li, Wen,Zhang, Liyuan,Ge, Xuehui,Xu, Biyi,Zhang, Weixia,Qu, Liangliang,Choi, Chang-Hyung,Xu, Jianhong,Zhang, Afang,Lee, Hyomin,Weitz, David A. The Royal Society of Chemistry 2018 Chemical Society reviews Vol.47 No.15

<P>Droplet microfluidics offers exquisite control over the flows of multiple fluids in microscale, enabling fabrication of advanced microparticles with precisely tunable structures and compositions in a high throughput manner. The combination of these remarkable features with proper materials and fabrication methods has enabled high efficiency, direct encapsulation of actives in microparticles whose features and functionalities can be well controlled. These microparticles have great potential in a wide range of bio-related applications including drug delivery, cell-laden matrices, biosensors and even as artificial cells. In this review, we briefly summarize the materials, fabrication methods, and microparticle structures produced with droplet microfluidics. We also provide a comprehensive overview of their recent uses in biomedical applications. Finally, we discuss the existing challenges and perspectives to promote the future development of these engineered microparticles.</P>

White Matter Microstructural Similarity and Diversity of Functional Constipation and Constipation-predominant Irritable Bowel Syndrome

( Jiaofen Nan ),( Liangliang Zhang ),( Qiqiang Chen ),( Nannan Zong ),( Peiyong Zhang ),( Xing Ji ),( Shaohui Ma ),( Yuchen Zhang ),( Wei Huang ),( Zhongzhou Du ),( Yongquan Xia ),( Ming Zhang ) 대한소화기기능성질환·운동학회(구 대한소화관운동학회) 2018 Journal of Neurogastroenterology and Motility (JNM Vol.24 No.1

Background/Aims The Rome III criteria separated chronic constipation into functional constipation (FC) and constipation-predominant irritable bowel syndrome (IBS-C), but some researchers questioned the partitioning and treated both as distinct parts of a continuum. The study aims to explore the similarity and diversity of brain white matter between FC and IBS-C. Methods The voxel-wise analysis of the diffusion parameters was used to quantify the white matter changes of female brains in 18 FC patients and 20 IBS-C patients compared with a comparison group with 19 healthy controls by tract-based spatial statistics. The correlations between diffusive parameters and clinical symptoms were evaluated using a Pearson’s correlation. Results In comparison to healthy controls, FC patients showed a decrease of fractional anisotropy (FA) and an increase of radial diffusivity (RD) in multiple major fibers encompassing the corpus callosum (CC, P = 0.001 at peak), external capsule (P = 0.002 at peak), corona radiata (CR, P = 0.001 at peak), and superior longitudinal fasciculus (SLF, P = 0.002 at peak). In contrast, IBS-C patients showed FA and RD aberrations in the CC (P = 0.048 at peak). Moreover, the direct comparison between FC and IBS-C showed only RD differences in the CR and SLF. In addition, FA and RD in the CC were significantly associated with abdominal pain for all patients, whereas FA in CR (P = 0.016) and SLF (P = 0.040) were significantly associated with the length of time per attempt and incomplete evacuation separately for FC patients. Conclusion These results may improve our understanding of the pathophysiological mechanisms underlying different types of constipation. (J Neurogastroenterol Motil 2018;24:107-118)

Characterization of Glycerol Dehydrogenase from Thermoanaerobacterium thermosaccharolyticum DSM 571 and GGG Motif Identification

( Liangliang Wang ),( Jiajun Wang ),( Hao Shi ),( Huaxiang Gu ),( Yu Zhang ),( Xun Li ),( Fei Wang ) 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.6

Glycerol dehydrogenases (GlyDHs) are essential for glycerol metabolism in vivo, catalyzing its reversible reduction to 1,3-dihydroxypropranone (DHA). The gldA gene encoding a putative GlyDH was cloned from Thermoanaerobacterium thermosaccharolyticum DSM 571 (TtGlyDH) and expressed in Escherichia coli. The presence of Mn(2+) enhanced its enzymatic activity by 79.5%. Three highly conserved residues (Asp(171), His(254), and His(271)) in TtGlyDH were associated with metal ion binding. Based on an investigation of glycerol oxidation and DHA reduction, TtGlyDH showed maximum activity towards glycerol at 60°C and pH 8.0 and towards DHA at 60°C and pH 6.0. DHA reduction was the dominant reaction, with a lower Km(DHA) of 1.08 ± 0.13 mM and Vmax of 0.0053 ± 0.0001 mM/s, compared with glycerol oxidation, with a Km(glycerol) of 30.29 ± 3.42 mM and Vmax of 0.042 ± 0.002 mM/s. TtGlyDH had an apparent activation energy of 312.94 kJ/mol. The recombinant TtGlyDH was thermostable, maintaining 65% of its activity after a 2-h incubation at 60°C. Molecular modeling and site-directed mutagenesis analyses demonstrated that TtGlyDH had an atypical dinucleotide binding motif (GGG motif) and a basic residue Arg(43), both related to dinucleotide binding.

Intrapuparial development and age estimation of Sarcophaga peregrina (Diptera: Sarcophagidae) for postmortem interval estimation

Li Liangliang,Zhang Yanan,Chen Yang,Guo Yi,Wang Yinghui,Hu Gengwang,Kang Chengtao,Jiangfeng Wang,Wang Yu 한국응용곤충학회 2023 Journal of Asia-Pacific Entomology Vol.26 No.2

Sarcophaga peregrina Robineau-Desvoidy, 1830 (Diptera: Sarcophagidae) is a widely distributed species in the Palearctic, Oriental and Australian regions. Numerous studies and case reports have confirmed the value of this species in forensic investigations, but methods for estimating the age of the intrapuparial period of this species are lacking. In this study, S. peregrina pupae were sampled at 16 ◦ C, 19 ◦ C, 22 ◦ C, 25 ◦ C, 28 ◦ C, 31 ◦ C, and 34 ◦ C. Morphological changes within the puparium were observed under a stereomicroscope. The results of the study showed that S. peregrina could complete its intrapuparial development at each of the seven tested constant temperatures. As the temperature increased, the average minimum duration of the intrapuparial period of S. peregrina decreased from 706.7 ± 28.1 h at 16 ◦ C to 170.7 ± 4.6 h at 34 ◦ C. The intrapuparial morphological changes of S. peregrina can be divided into 12 sub-stages. While some structures such as the compound eyes, mouthparts, antennae, thorax, legs, wings, and abdomen can be used individually to estimate intrapuparial age, we observed all these structures with local magnification photographs and classified the developmental process of these structures into 6–11 stages. The time range for the appearance of each sub-stage or structure was recorded in detail. The results of this study provide important basic data for estimating the minimum postmortem interval using the intrapuparial morphology of S. peregrina.

High performance proton-conducting solid oxide fuel cells with a layered perovskite GdBaCuCoO5+x cathode

Xiaozhen Zhang,Yuhua Jiang,Xuebing Hu,Liangliang Sun,Yihan Ling 대한금속·재료학회 2018 ELECTRONIC MATERIALS LETTERS Vol.14 No.2

Proton-conducting solid oxide fuel cell (H-SOFC) based on layered perovskite type GdBaCuCoO5+x (GBCC) cathodewas fabricated with in situ drop-coating BaZr0.1Ce0.7Y0.2O3−δ (BZCY) electrolyte membrane. The influences of Cu dopinginto Co sites of GdBaCo2O5+x on the electrical conductivity and conduction mechanism, thermal expansion propertyand electrochemical performance of cathode materials and corresponding single cell were investigated. Results show thatthe electrical conductivity decreased and the conduction mechanism would gradually transform to the semiconductor-likebehavior. A high maximum power density of 480 mW cm−2 was obtained for the anode supported NiO–BZCY/NiO–BZCY/BZCY/GBCC single cells with wet H2fuel at 700 °C. The corresponding polarization resistance was as low as 0.17 Ω cm2. The excellent electrochemical performance of as-prepared single cell indicates that GBCC is a good candidate of cathodematerials for H-SOFCs.