Low Temperature Synthesis of Mesoporous SiC in Dual-Confined Spaces via Magnesiothermic Reduction

Zeng-Rong Wang,Long Liu,Xue Zhang,Jia-Lin Xu,Qiang Sun 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2019 NANO Vol.14 No.9

Silicon carbide (SiC), especially mesoporous SiC has been in immense vogue for more than a decade because of its intriguing properties and wide applications. However, it is still challenging to synthesize mesoporous SiC with good structural integrality, large specific surface area and desirable porosity at a low temperature. In this study, we reported a "dual-confined spaces"-assisted synthesis of mesoporous SiC using well-assembled SiO2/carbon composite as precursor via a magnesiothermic reduction process. The well-crystallinity mesoporous SiC presented a mesopore structure with high specific surface area of 267.3 m2 g -1 and large mesopore size of ca. 10 nm can be directly fabricated at a temperature of at least 550 ℃ and the optimum synthesis temperature is 650 ℃. During the synthesis, mesoporous carbon matrix and a pressure-tight stainless steel reactor were served as "dual-confined spaces" to avoid the aggregation of silica and the silicon residue left in the final SiC sample. Furthermore, the as-prepared mesoporous SiC showed prominent performance as catalyst support for the reduction of 4-nitrophenol to 4-aminophenol.

Prognostic Significance of Beta-Catenin Expression in Patients with Esophageal Carcinoma: a Meta-analysis

Zeng, Rong,Duan, Lei,Kong, Yu-Ke,Wu, Xiao-Lu,Wang, Ya,Xin, Gang,Yang, Ke-Hu Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.15

Many studies have reported ${\beta}$-catenin involvement in the development of esophageal carcinoma (EC), but its prognostic significance for EC patients remains controversial. Therefore, we conducted this meta-analysis to explore the issue in detail. After searching PubMed, EMBASE, Web of Science, and Chinese Biomedical Literature Database, we included a total of ten relevant studies. We pooled the overall survival (OS) data using RevMan 5.2 software. The results showed that aberrant expression of ${\beta}$-catenin was associated with a significant increase of mortality risk (hazard ratio 1.71, 95%CI 1.46-2.01; p<0.00001). Subgroup analyses further suggested that aberrant expression of ${\beta}$-catenin resulted in poor OS of EC patients regardless of histological type of EC, study location or criteria for aberrant expression of ${\beta}$-catenin, and the sensitivity analyses revealed that the result was robust. The meta-analysis revealed that aberrant expression of ${\beta}$-catenin could be a predicative factor of poor prognosis for EC patients.

Influence of overhead transmission line on grounding impedance measurement of substation

Zeng, Rong,He, Jinliang,Lee, Jaebok,Chang, S.,Tu, Youping,Gao, Yanqing,Zou, Jun,Guan, Zhicheng IEEE 2005 IEEE transactions on power delivery Vol.20 No.2

How to precisely measure the grounding impedance of large-scale substations is a fundamental guarantee for the safe operation of power systems. If the ground wires were connected to the grounding grid, these ground wires would shunt a part of the injected measuring current and allow the measured grounding impedance to be smaller than the actual impedance of the grounding system. Based on an actual 500-kV grounding system, this paper discusses how to analyze the influence of the overhead ground wire on the measured grounding impedance and how to obtain the real grounding impedance of the grounding system. A numerical analysis model considering the grounding system, the transmission lines, towers, and their grounding devices, based on the multilayer soil model analyzed from field test data of apparent soil resistivity, was constructed to analyze the influence of ground wires and tower grounding resistances on grounding impedance, and the general effects of different parameters, such as tower impedance, grounding impedance, and circuits of transmission lines, were analyzed. The real grounding impedance of the substation with connected overhead ground wires was validated, and some useful results have been obtained, based on the field-measured values and numerical analysis.

중국 HVDC 사업 및 연구개발 어떻게 추진되고 있는가?

Rong Zeng,Wang Wei,Hao Hu,이동일,신구용 대한전기학회 2016 전기의 세계 Vol.65 No.6

Effect of Bond Linkage on In vitro Drug Release and Anti-HIV Activity of Chitosan-Stavudine Conjugates

Rong Zeng,Renzhong Qiao,Zehu Wang,Hongran Wang,Liqiang Chen,Lin Yang,Liming Hu,Zelin Li 한국고분자학회 2012 Macromolecular Research Vol.20 No.4

Two kinds of chitosan-stavudine (d4T) conjugates, chitosan-O-isopropyl-5'-O-d4T monophosphate conjugate (Cs-P-d4T) with a phosphoramide linkage and chitosan-5'-O-succinyl-d4T conjugate (Cs-S-d4T) with a succinic spacer, were synthesized using an Atherton-Todd reaction and carbodiimide coupling reaction, respectively, and then structurally characterized. Their in vitro drug release behaviors and anti-human immunodeficiency virus (HIV) activity were investigated and compared. Both of the chitosan-d4T conjugates more strongly prefer to release corresponding d4T derivatives rather than free d4T in a prolonged manner but have different hydrolysis routes. The anti-HIV activity and cytotoxicity evaluated in the MT4 cell line revealed that the anti-HIV selectivity index was in the following order: Cs-P-d4T > d4T >> Cs-S-d4T since the released d4T-5'-(O-isopropyl) monophosphate from Cs-P-d4T can bypass the rate-limiting bottleneck of nucleoside phosphorylation, while the released 5'-O-succinyl-d4T from Cs-Sd4T has to be hydrolyzed to d4T and then successively phosphorylated to its active form to exert antiviral activity. The results suggested that constructing a chitosan-nucleoside reverse transcriptase inhibitor (NRTI) conjugate with a phosphoramide linkage may be an efficient approach for improving NRTI therapy efficacy in antiretroviral treatment.

五代吏部選人文書初探

曾育榮(Zeng Yu-rong) 경북대학교 아시아연구소 2011 아시아연구 Vol.- No.13

五代시기, 吏部에서 6品 이하의 官員을 選任할 때는 대체적으로 庸代의 銓選제도를 답습하였다. 그러나 五代시기는 戰亂이 끊이지 않아 사회가 안정되지 않아 장기간 銓選제도가 규범화 되지 않았기 때문에 매우 혼탁하였다. 이와 같은 상황을 변화시키기 위해 後唐시기부터 各朝는 모두 여러 가지 조치를 취하여 吏部選人文書에 眞僞가 섞인 상황을 변화시키고자 하였다. 그 중 가장 중요한 조치의 하나가 吏部에서 選人文書에 대한 심사를 더욱 엄격히 하는 것이었다. 그래서 選人文書의 종류가 9種으로 늘어났고 이것은 唐代에 비해 훨씬 많아진 것이었다. 그 중에서도 選人의 기본적인 자질에 대한 자료가 매우 상세해졌다. 구체적으로 보면, 첫째, 초기 선택단계에서 選人이 제출해야 하는 문서는 네 가지가 있었다. ⓛ 解狀으로, 여기에는 選人의 출신, 3대의 가족상황, 鄕貫, 骨肉, 在朝親情, 年齒形貌, 考覈資序, 優劣課最, 罷職年月 등이 포함된 官員 개인 이력을 상세히 나타낸 문서였다. 매년 5월에는 選格科限에 부합하는 選人은 “銓狀”이라는 申請表를 써서 本郡 혹은 任所에 보내 府川 혹은 本司 장관이 吏部의 選格樣式에 따라 심사의견을 쓴 다음 다시 選人에게 주었다. ② 歷子로서, 이것은 吏部에서 官員이 역임할 때 주는 사인과 도장을 찍은 문서를 말하는데, 여기에는 관원이 上任하는 月日과 累任하는 月日 및 임기의 治積 등이 적혀있다. ③ 解由로서, 이것은 관원이 罷任될 때 각 지역 州府의 관리와 여러 司의 長官들이 제출하는 문서로서, 여기에는 罷任月日, 戶口增減과 세금 수금 액수 등이 적혀있다. ④ 考牒으로, 이것은 관원의 역대 考課 등급 기록으로서 관원이 일정시기 사업한 실적의 최종 평가결과이다. 둘째, 注判 단계에 選人이 제출해야할 문서에는 세 가지가 있다. ① 告身, 즉 吏部가 官員에게 수여하는 일종의 憑證으로서 後唐시기인 長興元年(930년) 5월에 시작하였다. 여기에는 選人이 銓司에게 제공한 告身, 注明하여 보관해야할 名銜, 選人의 三代情況, 有無出身, 歷任告敕, 逐任考數 등이 포함되어 있다. ② 告敕, 즉 官員의 위임장으로서 注判 전에 選人이 歷任告敕을 告身 내에 붙여서 吏部南曹에게 바쳐 審覈을 받는다. ③ 公憑, 이것은 選人이 문서를 분실 했을 때의 증명이거나, 州府의 長官이 冤案을 심리할 때 縣官이 작성한 증명이거나, 관련 기구에서 官員에게 보낸 減選증명이거나, 吏部 南曹가 選人이 바친 歷任사실을 나타내는 문서를 받고나서 떼어준 수거이다. 마지막으로 引驗 단계에서 銓司勘覈한 選人文書에는 두 종류가 있다. ① 家狀, 즉 選人의 郡縣鄕里, 父祖官名, 內外族姻, 年齒形式 등을 적은 家庭證明이다. ② 保狀, 즉 選人 상호간에 보증한 문서와 選人을 잘 아는 京官이 제출한 보증 문서이다. During the Five Dynasty, Ministry of Personnel still adopted the Tang Dynasty’s Personnel Selecting System for those official personnel whose positions were lower than Liuping position. However, as a result of the war affairs and the turbulent and unsafe social situation, the phenomena of forgery candidates and cheating in the selection were very common as the Personnel Selecting System was not supervised properly for a long period. Every Dynasty had taken some measures to punish and prevent such cheating behaviors in order to make the Personnel Selecting System step into the right path since the Later Tang Dynasty. Among those measures, the most significant one was to check Candidates’ testing paper in a more stringent process. The kinds of Selection Testing Paper had been increased to nine, which were much more than the number of Dang Dynasty. And it had required candidates to supply the detailed personal information. To put it more specifically, at the first phase of selection, a candidate should supply four types of credentials. ① Xiezhuang, it included political achievements, financial contribution to the government, and final evaluation during his term of office. For the personal information, it contained a candidate’s family status, his ancestor’s basic information, his off springs, and his relatives who were working in the government, personal image description, the job he had applied for, his advantages and disadvantages, and his resignation date. Every May, those qualified candidates would fill in the application forms, and then the leaders of the local government would give the comments in those forms. ② Lizi, it was a kind of credential, which was presented by the Ministry of Personnel. It contained the date when the candidate should proceed to take up one’s post and when he should leave the post. It also included the candidate’s historic achievements. ③ Jieyou, it was a kind of credential, which was given by the candidate’s higher-ups. The content still was about the candidate’s performing achievements during his term of office. ④ Kaodie, it was a kind of credential which was about the candidate’s historic testing records and working evalutions in his previous term of the office. Then, at the second phase of selection, the candidates should submit 3 types of credentials. They are specifically ① Gaoshen, a kind of certificate conferred by the Ministry of Official Personnel Affairs. Since the May of the first year of Changxing reign of Later Tang Dynasty, the Gaoshen submitted by the candidates to Quansi(the officials in charge of selection) should state clearly information such as the official title, the family condition within three generations, the social connections, and so forth. ② Gaochi, namely the credential of appointment. The candidate should submit Gaoshen with Gaochi of successive posts attached to Ministry of Official Affairs for examination and verification. ③ Gongping, the testimony for missing certificates or the testimony for grievance cases issued by the top officials of the prefecture or the receipt issued by the Ministry of the Official Affairs for receiving candidates’ documents of successive posts. Finally, two types of credentials should be submitted at the final phase of the selection: ① Jiangzhuang, the record of such family information as the predecessers’ officials titles, marriages within and beyond the clan and so forth. ② Baozhuang, the surety document presented by other candidates or the superior officials who are familiar the candidate.

A Real-Time Vibration Frequency Measurement System of Bridge Pier

Yao-Ming Hong,Jian-Rong Zeng,Yao-Chiang Kan,Hsueh-Chun Lin 보안공학연구지원센터 2014 International Journal of Hybrid Information Techno Vol.7 No.6

This study developed a real-time remote monitoring system (RTRMS) to receive the vibration frequency of bridge pier. The system included a front station and a middle station. A multi-hop wireless routing is employed to transmit the data from the front to the middle station. The front station includes a receiver equipped to receive the vibration frequency, and a wireless sensor network to transmit the data. The middle station is designed by an embedded system for storing the data. The pressure test shows that the loss rate of received data is less than 0.6%. The consuming power of one day is 3 ampere hours in the front station and 30 ampere hours in the middle station if the 12 voltage battery is used.

Protective effect of adiponectin on paraquat-induced pulmonary fibrosis in mice

Rong Yao,Yarong He,Zhi Zeng,Zongan Liang,Yu Cao 대한독성 유전단백체 학회 2015 Molecular & cellular toxicology Vol.11 No.2

Pulmonary fibrosis (PF) is the most common complication of paraquat (PQ) toxicity, which lacks an effective treatment. This study aimed to investigate whether exogenous administration of globular adiponectin (APN) isoform provided protection against PQ-induced PF, and examined the possible mechanisms underlying these effects. Eighty BALB/C mice were randomly divided into control, PQ, lowdose APN, and high-dose APN groups. Human lung WI-38 fibroblasts were similarly divided into control, PQ, and APN groups and examined at 24 h, 48 h, and 72 h after PQ exposure. Hematoxylin and eosin (HE) and Masson trichrome staining were used to compare the histopathologic changes in the mouse lung tissues. Western blot and real-time quantitative-PCR (RTPCR) were used to measure the protein and mRNA expression of transforming growth factor β1 (TGF-β1) in mice lung tissues and α-SMA, type III collagen, and NF-κB p65 in lung fibroblasts. Dihydroethidium (DHE) was used to detect intracellular superoxide anion (O2-) in fibroblasts. APN administration significantly ameliorated PQ-mediated fibrosis histologically and reduced the protein and mRNA expression levels of TGF-β1 in mouse lung tissues in a dose-dependent manner (P<0.05). When fibroblasts were pretreated with APN, the expression of α-SMA and NF-κB p65 were down-regulated, and O2- decreased. Expression of the anti-inflammatory factor IL-1Ra was upregulated following PQ exposure (P<0.05). This study revealed the beneficial effects of APN against PQ-induced PF, which may have occurred through suppression of NF- κB dependent inflammatory and TGF-β1 mediated fibrotic events

REACTIVE BLENDING OF POLYCARBONATE WITH EPOXY RESIN : I. CURING BEHAVIOR AND SUPERMOLECULAR STRUCTURE ANALYSIS

Rong, Minzhi,Zeng, Hanmin 한국재료학회 1995 Fabrication and Characterization of Advanced Mater Vol.1 No.3

An epoxy resin based on DGEBA has been modified with polycarbonate(PC) by a new reactive blending method which can result in a single phase blend. The supermeolecular structurte of PC/epoxy blends can be controlled by these reactive blending process, which utilize the intermolecular interaction via hydrogen bonding or chemical reaction between the components. The kinetic of the curing reaction of the neat resin and of PC/epoxy blends were analyzed by dynamic DSC. Combination feature of dynamic mechanical spectra and infrared spectra of products can give an evident characterization of their supermolecular structure.

Molecular features and functional studies of transcription factor, Cap ‘n’ collar C, in the brown planthopper, Nilaparvata lugens Stål (Hemiptera Delphacidae)

Zeng Bin,Feng Ze-Rui,Liu Ya-Ting,Chen Fu-Rong,Wang Shuai,Wu Shun-Fan,Yu Zhi-Tao,Gao Cong-Fen 한국응용곤충학회 2022 Journal of Asia-Pacific Entomology Vol.25 No.4

Cap ‘n’ collar C (CncC), a transcription factor, plays a vital role in the development of insect resistance by regulating the expression of multiple detoxifying genes. Clarifying the molecular characteristics of CncC and its pathway regulating insecticide resistance will aid the development of integrated pest control strategies. Here we cloned and identified the molecular feature of CncC genes from the brown planthopper (BPH), Nilaparvata lugens (Stål), (Hemiptera Delphacidae). The full-length open reading frame of NlCncC was 3015 nucleotides with 1005 amino acids. The deduced amino acid sequence has a high similarity with other insect homologs and contains the characteristic Cnc/bZip domain architecture. Functional studies showed that silencing NlCncC by RNA interference (RNAi) could downregulate the transcript expression of NlCYP6ER1, NlCYP6CW1, and NlCYP6AY1, which increase the susceptibility to imidacloprid in N. lugens. The identification of molecular characteristics of NlCncC and func tional studies in this paper will contribute to designing effective control strategies for N. lugens.