Effect of Cr2O3 on the viscosity and structure of slag (or glass) of CaO-MgO-Al2O3-SiO2 system

Wang Yifan,Wang Yici,Zhang Yunhao,Chai Yifan,Zhao Fengguang,Luo Guoping 한국화학공학회 2023 Korean Journal of Chemical Engineering Vol.40 No.7

The glass-ceramics of CaO-MgO-Al2O3-SiO2-Cr2O3 system was prepared by melting method using blast furnace slag, low-carbon ferrochrome alloy slag and quartz sand as raw materials, and the effect of Cr2O3 on the viscosity and structure of slag (or glass) of CaO-MgO-Al2O3-SiO2 (CMAS) system at high temperature was studied. The Urbain viscosity prediction model was established and optimized, and the effect of Cr2O3 on the structure of slag (or glass) was studied by Raman spectroscopy. The results show that when the mass fraction of Cr2O3 is in the range of 0.85–2.05%, the viscosity of slag (or glass) of CMAS system decreases with the increase of Cr2O3 content. The average relative errors between the experimented viscosity value and the calculated viscosity value obtained by using the optimized Urbain model are less than 20%, which is effective and universal for the viscosity prediction of slag (or glass) of CaO-MgO-Al2O3-SiO2-Cr2O3 system. With the increase of Cr2O3 content, the complex silicon oxygen tetrahedrons (Q3) disintegrate into a larger number of simple silicon oxygen tetrahedrons (Q0, Q1, Q2), resulting in the sparse structure of the melt network and a decrease in macroscopic viscosity.

Higher order electro-magneto-elastic free vibration analysis of piezomagnetic nano panel

Wang Guoping,Hao Huadong,Arefi Mohammad 한국CDE학회 2021 Journal of computational design and engineering Vol.8 No.3

This paper investigates electro-magneto-elastic free vibration responses of piezomagnetic cylindrical nano panel subjected to electro-magneto-mechanical loads based on third-order theory. Third-order shell theory is used for description of the displacement field. The zero transverse shear strains are obtained using the third-order displacement field. Hamilton’s principle is employed to obtain the governing equations of motion. The nano panel is subjected to a coupling of magnetic and electric loads, including a linear function along with the thickness direction and a 2D function along with the axial and circumferential directions. To account the effect of nanoscale in governing equations, the Eringen nonlocal elasticity theory is used. The numerical results are obtained to investigate the impact of significant parameters such as axial and circumferential mode numbers, the nanoscale parameter, applied electromagnetic potentials, and length-to-radius ratio. It is concluded that an increase in initial electric potential and a decrease in magnetic potential lead to an increase in natural frequencies of the nano panel.

Biochemical Properties and Physiological Roles of NADP-Dependent Malic Enzyme in Escherichia coli

Baojuan Wang,Peng Wang,Enxia Zheng,Xiangxian Chen,Hanjun Zhao,Ping Song,Ruirui Su,Xiaoning Li,Guoping Zhu 한국미생물학회 2011 The journal of microbiology Vol.49 No.5

Malic enzymes catalyze the reversible oxidative decarboxylation of L-malate using NAD(P)^+ as a cofactor. NADP-dependent malic enzyme (MaeB) from Escherichia coli MG1655 was expressed and purified as a fusion protein. The molecular weight of MaeB was about 83 kDa, as determined by SDS-PAGE. The recombinant MaeB showed a maximum activity at pH 7.8 and 46°C. MaeB activity was dependent on the presence of Mn^(2+) but was strongly inhibited by Zn^(2+). In order to understand the physiological roles, recombinant E. coli strains (icdNADP/ΔmaeB and icdNAD/ΔmaeB) containing NADP-dependent isocitrate dehydrogenase (IDH), or engineered NAD-dependent IDH with the deletion of the maeB gene, were constructed using homologous recombination. During growth on acetate, icd^(NAD)/ΔmaeB grew poorly, having a growth rate only 60% that of the wild-type strain (icd^(NADP)). Furthermore, icd^(NAD)P/ΔmaeB exhibited a 2-fold greater adaptability to acetate than icdNAD/ΔmaeB, which may be explained by more NADPH production for biosynthesis in icd^(NAD)P/ΔmaeB due to its NADP-dependent IDH. These results indicated that MaeB was important for NADPH production for bacterial growth on acetate. We also observed that MaeB activity was significantly enhanced (7.83-fold) in icd^(NAD), which was about 3-fold higher than that in icd^(NADP), when switching from glucose to acetate. The marked increase of MaeB activity was probably induced by the shortage of NADPH in icd^(NAD). Evidently, MaeB contributed to the NADPH generation needed for bacterial growth on two carbon compounds.

Prognostic Threshold of Neuroendocrine Differentiation in Gastric Carcinoma: a Clinicopathological Study of 945 Cases

Zou, Yi,Chen, Linying,Wang, Xingfu,Chen, Yupeng,Hu, Liwen,Zeng, Saifan,Wang, Pengcheng,Li, Guoping,Huang, Ming,Wang, Liting,He, Shi,Li, Sanyan,Jian, Lihui,Zhang, Sheng The Korean Gastric Cancer Association 2019 Journal of gastric cancer Vol.19 No.1

Purpose: The significance of neuroendocrine differentiation (NED) in gastric carcinoma (GC) is controversial, leading to ambiguous concepts in traditional classifications. This study aimed to determine the prognostic threshold of meaningful NED in GC and clarify its unclear features in existing classifications. Materials and Methods: Immunohistochemical staining for synaptophysin, chromogranin A, and neural cell adhesion molecule was performed for 945 GC specimens. Survival analysis was performed using the log-rank test and univariate/multivariate models with percentages of NED ($P_{NED}$) and demographic and clinicopathological parameters. Results: In total, 275 (29.1%) cases were immunoreactive to at least 1 neuroendocrine (NE) marker. GC-NED was more common in the upper third of the stomach. $P_{NED}$, and Borrmann's classification and tumor, lymph node, metastasis stages were independent prognostic factors. The cutoff $P_{NED}$ was 10%, beyond which patients had significantly worse outcomes, although the risk did not increase with higher $P_{NED}$. Tumors with ${\geq}10%$ NED tended to manifest as Borrmann type III lesion with mixed/diffuse morphology and poorer histological differentiation; the NE components in this population mainly grew in insulae/nests, which differed from the predominant growth pattern (glandular/acinar) in GC with <10% NED. Conclusions: GC with ${\geq}10%$ NED should be classified as a distinct subtype because of its worse prognosis, and more attention should be paid to the necessity of additional therapeutics for NE components.

Prognostic Threshold of Neuroendocrine Differentiation in Gastric Carcinoma: a Clinicopathological Study of 945 Cases

Yi Zou,Linying Chen,Xingfu Wang,Yupeng Chen,Liwen Hu,Saifan Zeng,Pengcheng Wang,Guoping Li,Ming Huang,Liting Wang,Shi He,Sanyan Li,Lihui Jian,Sheng Zhang 대한위암학회 2019 Journal of gastric cancer Vol.19 No.1

Purpose: The significance of neuroendocrine differentiation (NED) in gastric carcinoma (GC) is controversial, leading to ambiguous concepts in traditional classifications. This study aimed to determine the prognostic threshold of meaningful NED in GC and clarify its unclear features in existing classifications. Materials and Methods: Immunohistochemical staining for synaptophysin, chromogranin A, and neural cell adhesion molecule was performed for 945 GC specimens. Survival analysis was performed using the log-rank test and univariate/multivariate models with percentages of NED (PNED) and demographic and clinicopathological parameters. Results: In total, 275 (29.1%) cases were immunoreactive to at least 1 neuroendocrine (NE) marker. GC-NED was more common in the upper third of the stomach. PNED, and Borrmann's classification and tumor, lymph node, metastasis stages were independent prognostic factors. The cutoff PNED was 10%, beyond which patients had significantly worse outcomes, although the risk did not increase with higher PNED. Tumors with ≥10% NED tended to manifest as Borrmann type III lesion with mixed/diffuse morphology and poorer histological differentiation; the NE components in this population mainly grew in insulae/nests, which differed from the predominant growth pattern (glandular/acinar) in GC with <10% NED. Conclusions: GC with ≥10% NED should be classified as a distinct subtype because of its worse prognosis, and more attention should be paid to the necessity of additional therapeutics for NE components.

Pharmacokinetic, metabolic stability, plasma protein binding and CYP450s inhibition/induction assessment studies of N-(2-pyridylmethyl)-2- hydroxiymethyl-1-pyrrolidinyl-4-(3-chloro-4-methoxy-benzylamino)-5- pyrimidine-carboxamide as potential type 5 phos

Haijun Qu,Xiaoxiao Hu,Xiaoli Shi,Chuan Wang,Longyuan Wang,Guoping Wang 한국통합생물학회 2019 Animal cells and systems Vol.23 No.3

N-(2-pyridylmethyl)-2-hydroxiymethyl-1-pyrrolidinyl-4-(3-chloro-4-methoxy-benzylamino)-5- pyrimidine-carboxamide (NHPPC) is a new potential of type 5 phosphodiesterase (PDE5) inhibitors, synthesized from the avanafil analogue for the treatment of erectile dysfunction. The targets of this article were to assess plasma protein binding, liver microsomal metabolic stability, inhibition and induction on cytochrome P450 isozymes and the pharmacokinetics of NHPPC. Equilibrium dialysis technique was applied to determine Plasma protein binding (PPB) and NHPPC was evaluated in male Sprague–Dawley rats and Beagle dogs in vivo pharmacokinetic. The NHPPC was highly bound to plasma proteins in rats, dogs and human tested and the mean values for PPB rate were 96.2%, 99.6% and 99.4%, respectively. After in vitro liver microsomes incubated for 60 min, the percent remaining of NHPPC was 42.8%, 0.8% and 42.0% in rats, dogs and human, respectively. In vitro intrinsic clearance was found to be 0.0233, 0.1204 and 0.0214 mL/min/mg protein in rat, dog and human liver microsomes of NHPPC, respectively. NHPPC showed no significant inhibitory effects on major CYP450 enzymes, and had no significant induction potential on CYP1A2 and CYP3A4. Following oral administration in rats and dogs, tmax was 6 and 0.5 h, respectively. The clearance for NHPPC was 1.19 and 1.46 L/h/kg in rats and dogs, respectively. And absolute bioavailability in rat and dog were approximately 34.5% and 53.1%, respectively. These results showed that NHPPC has a good development prospect.

Effects of Enzymolysis on the Functional Ingredient Contents and Antioxidant Activities of Aqueous Enzymatic Extracts from Rice Bran and Correlation Analysis

Yuxin Wang,Guoping Yu,Anmin Sun,Xinghang Cai,Chonghui Yue 한국식품과학회 2015 Food Science and Biotechnology Vol.24 No.5

Effects of different hydrolytic conditions on functional ingredient contents and antioxidant activities of aqueous enzymatic extracts from rice bran (AEERB) were evaluated and correlations were determined. After trypsin hydrolysis under weak alkalescent conditions, the soluble protein, total phenolic, α-tocopherol, and γ-oryzanol contents of AEERB were increased. Excessively high temperatures (>60℃) and long hydrolysis times (>2.0 h) were not suitable for enzymatic hydrolysis. The free radical scavenging activity, ferric reducing/antioxidant power, lipid peroxidation inhibition activity, and total antioxidant activity were used for evaluation of the antioxidant activity. AEERB displayed an antioxidant activity and correlations of concentration levels of functional ingredients with antioxidant activity were significantly (p<0.05) positive.

Characteristics and Causes of Extreme Rainfall Induced by Binary Tropical Cyclones over China

Mingyang Wang,Fumin Ren,Yanjun Xie,Guoping Li,Ming-Jen Yang,Tian Feng 한국기상학회 2021 Asia-Pacific Journal of Atmospheric Sciences Vol.57 No.2

Binary tropical cyclones (BTC) often bring disastrous rainfall to China. From the viewpoint of the extreme of the BTC maximum daily rainfall, the characteristics of BTC extreme rainfall (BTCER) during 1960–2018 are analyzed, using daily rainfall data; and some representative large-scale mean flows, in which the associated BTCs are embedded, are analyzed. Results show that the frequency of BTCER shows a decreasing trend [−0.49 (10 yr)−1] and is mainly distributed within the BTC heavy rainstorm interval (100 mm≤ BTCER <250 mm). BTCER occurs mostly from July to September with a peak in August. Three BTCER typical regions— Minbei, the Pearl River Delta (PRD), and Taiwan—are identified according to the clustering of stations with high BTCER frequency and large BTCER. A further analysis of the 850-hPa BTC composite horizontal wind and water vapor flux over the PRD region shows the existence of two water vapor transport channels, which transport water vapor to the western tropical cyclone. In the first of these channels, the transport takes place via the southwest monsoon, which accounts for 58% of the total moisture, and an easterly flow associated with eastern tropical cyclone accounts for the remaining 42%. Binary tropical cyclones (BTC) often bring disastrous rainfall to China. From the viewpoint of the extreme of the BTC maximum daily rainfall, the characteristics of BTC extreme rainfall (BTCER) during 1960–2018 are analyzed, using daily rainfall data; and some representative large-scale mean flows, in which the associated BTCs are embedded, are analyzed. Results show that the frequency of BTCER shows a decreasing trend [−0.49 (10 yr) −1 ] and is mainly distributed within the BTC heavy rainstorm interval (100 mm ≤ BTCER <250 mm). BTCER occurs mostly from July to September with a peak in August. Three BTCER typical regions— Minbei, the Pearl River Delta (PRD), and Taiwan—are identified according to the clustering of stations with high BTCER frequency and large BTCER. A further analysis of the 850-hPa BTC composite horizontal wind and water vapor flux over the PRD region shows the existence of two water vapor transport channels, which transport water vapor to the western tropical cyclone. In the first of these channels, the transport takes place via the southwest monsoon, which accounts for 58% of the total moisture, and an easterly flow associated with eastern tropical cyclone accounts for the remaining 42%.

Dynamic Magnetic Field Measurement in the Air Gap of Magnetic Bearings Based on FBG-GMM Sensor

Liu Jiayi,Ding Guoping,Zhou Zude,Wang Huaqiang 한국광학회 2015 Current Optics and Photonics Vol.19 No.6

Magnetic field in magnetic bearings is the physical medium to realize magnetic levitation, the distributionof the magnetic field determines the operating performance of magnetic bearings. In this paper, a thin-sliceFiber Bragg Grating-Giant Magnetostrictive Material magnetic sensor used for the air gap of magneticbearings was proposed and tested in the condition of dynamic magnetic field. The static property of thesensor was calibrated and a polynomial curve was fitted to describe the performance of the sensor. Measurement of dynamic magnetic field with different frequencies in magnetic bearings was implemented. Comparing with the finite element simulations, the results showed the DC component of the magneticfield was detected by the sensor and error was less than 5.87%

Synthesis of Dithiolopyrrolone Derivatives and Their Leukocyte-Increasing Activities

Chungang Li,Yiping Sun,Guoping Wang,Xiangduan Tan 대한화학회 2014 Bulletin of the Korean Chemical Society Vol.35 No.12

In search of new antileukopenia agents, twenty dithiolopyrrolone derivatives were synthesized and evaluated for their leukocyte-increasing activities in normal mice. Among the synthesized compounds 4-23, compounds 5 and 6 showed significant leukocyte-increasing activity ( p < 0.01), and compounds 4, 9 and 16 had a moderate effect ( p < 0.05). Compound 5 also displayed stronger leukocyte-increasing activity than that of the positive recombinant human granulocyte colony stimulating factor (rhG-CSF). Above all, compound 5 would be a potential antileukopenia agent which deserved further research.