Analysis of Total Factor Productivity in the Chinese Manufacturing Sector: Focusing on Firm Ownership Types

Tian Wen,유태환,배성일 한국산업경제학회 2022 산업경제연구 Vol.35 No.1

This study reinvestigates Total Factor Productivity (TFP) growth in the Chinese manufacturing sector from 1999 to 2016 and estimates TFP growth in different ownership types over the period 2004 to 2011. First, this study employs the Malmquist index since it is possible to compare TFP growth among manufacturing sectors and identify the main source of TFP growth. The estimated results show that the average TFP growth among Chinese manufacturing industries is 6.4% per year, and technical progress is found to be the main source of TFP growth. The efficiency change in the Chinese manufacturing sector is poor due to research and development effects, and there is a significant disparity in terms of TFP growth among the 28 manufacturing industries in China. Second, although the estimated results show that TFP growth in all ownership types is positive, there is a significant disparity among different ownership types due to various causes. Overall, the findings from this study provide an optimistic expectation for the future development of the Chinese manufacturing sector based on technical progress, while Chinese manufacturing firms need to pay much attention to promoting their efficiency in the future.

Analysis of China’s Total Factor Productivity Performance Based on Cross-economy Comparison

Tian, Wen,Bae, Sungl-Il(배성일) 한국산업경제학회 2021 산업경제연구 Vol.34 No.1

본 연구는 1992년부터 2018년까지의 기간에 대하여 중국의 총요소생산성에 대한 성장률 및 수준, 그리고 총요소생산성의 경제 성장에 대한 기여도를 분석하였다. 첫째로, 총요소생산성의 성장률은 성장회계 프레임워크를 통해 솔로우 잔차를 이용하여 추정하였다. 이에 대한 분석 결과, 총요소생산성의 증가가 중국 경제 성장의 중요한 요인으로 작용하였지만, 최근 몇 년 동안에는 총요소생산성의 성장이 다소 둔화된 것으로 확인되었다. 둘째로, 국가 간 비교분석에서는 중국의 총요소생산성의 증가가 다른 국가들과 비교하여 매우 빠르고 경제성장에 훨씬 큰 역할을 하는 것으로 나타났다. 더불어, 중국의 총요소생산성 수준이 현재는 다른 국가들과 비교하여 상대적으로 낮으나 향후 상당히 더 높은 수준에 도달할 잠재성을 갖추고 있음을 보여주었다. 마지막으로, 본 연구의 실증분석 결과에서는 중국의 총요소생산성 성장이 장기적으로 지속가능하나 이와 더불어, 총요소생산성 수준의 향상이 필수적이고 장기적인 과업이라는 것을 보여주었다. This study aims to investigate China’s total factor productivity (TFP) growth rate, TFP level, and TFP growth’s contribution to the country‘s economic growth over the 1992-2018 period. Applying the growth accounting framework, the TFP growth rate is estimated by using the Solow residual. The results show that TFP growth has become an important source of China’s economic growth but there has been a mild slowdown in China’s TFP growth in recent years. A cross-economy comparison shows that TFP growth in China is both much faster and plays a more significant role in its economic growth, as compared with other noteworthy economies. The results also indicate that China’s TFP level, while still being relatively low, has the potential to reach significantly higher levels in the future. The empirical analysis in this study tends to support the argument that China’s growth is sustainable in the long run, but also indicates that improving its TFP level will be a necessary and long-term task.

Screening and Characterization of an Aerobic Nitrifying-denitrifying Bacterium from Activated Sludge

Xiaofan Qiu,Tianwen Wang,Xiaomin Zhong,Guocheng Du,Jian Chen 한국생물공학회 2012 Biotechnology and Bioprocess Engineering Vol.17 No.2

Taking advantage of the good biocompatibility and high efficiency of nitrogen removal with microbes,nitrifying and denitrifying bacteria, are becoming increasingly more widely used for wastewater treatment and prevention of eutrophication. In this research, an aerobic nitrifying-denitrifying bacterium was successfully screened from activated sludge and identified as Pseudomonas sp. (CCTCC No M2010209) by the 16S rDNA sequence. The activity verification confirmed its nitrifying-denitrifying capability of removing ammonium, nitrate and nitrite nitrogen. The types of carbon sources and carbon-nitrogen ratio greatly influenced the removal efficiency of NH4+-N and NO3−-N. When the initial concentrations of NH4+-N and NO3−-N in synthetic wastewater were less than 70 and 50mg/L, the nitrogen removal rates reached 94 and 90% in 9 h, respectively. Preliminary comparisons of nitrogen removal capacity between this isolate and other commercial preparations in the treatment of synthetic wastewater revealed its promising potential to be used in the actual wastewater treatment.

Synthesis of mesoporous silica MCM-41 using sodium silicate derived from copper ore tailings with an alkaline molted-salt method

Pingfeng Fu,Tianwen Yang,Jie Feng,Huifen Yang 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.29 No.-

The alkaline molten-salt method was taken to effectively extract silicon from the copper ore tailings at500–600 8C. The extraction rate of SiO2 and Fe2O3 was ca. 82% and below 2%, respectively. Hematite wasnot converted to soluble NaFeO2 in low temperature NaOH–NaNO3 molten system. Mesoporous MCM-41 was synthesized using a hydrothermal method with the extracted Na2SiO3. The analysis of smallangle XRD, N2 adsorption–desorption and HRTEM showed that the silica sample had a regular hexagonalstructure of typical mesoporous MCM-41. The obtained MCM-41 silica had a BET specific surface area of946.68 m2/g and mesopore volume of 0.76 cm3/g.

Development and Application of Polymorphic SSR Markers in Luffa cylindrica

Junjie Cui,Zhen Lv,Tianwen Yang,Jing Wang,Yu Hong 한국원예학회 2022 원예과학기술지 Vol.40 No.5

Two published genomes of Luffa cylindrica, ‘SG2019’ and ‘SO3’, were used to develop polymorphic SSR markers for L. cylindrica by searching and comparing the SSR motifs at the same site in the two genomes. Based on the SSR search conditions and primer design criteria, 2130 polymorphic SSR markers for L. cylindrica were developed. The main motif type was dinucleotide, accounting for 80.28% of the total; the main motif units were AT/AT and AAT/ATT, accounting for 87.80% of the total. Furthermore, 40 polymorphic SSR markers developed in this study were randomly selected and amplified in 24 Luffa samples. According to the results, the 40 polymorphic SSR markers showed an amplification rate of 100% and a polymorphism rate of 80%. Cluster analysis classified the 24 Luffa samples into two main groups, L. cylindrica and L. acutangula. Overall, the polymorphic SSR markers developed in this study display a high polymorphic rate and reliable utilization value.

Optimization and High-level Expression of a Functional GST-tagged rHLT-B in Escherichia coli and GM1 Binding Ability of Purified rHLT-B

Xingyuan Ma,Wenyun Zheng,Tianwen Wang,Dongzhi Wei 한국미생물학회 2006 The journal of microbiology Vol.44 No.3

The Escherichia coli heat-labile enterotoxin B subunit (HLT-B) is one of the most powerful mucosal immunogens and known mucosal adjuvants. However, the induction of high levels of HLT-B expression in E. coli has proven a difficult proposition. Therefore, in this study, the HLT-B gene was cloned from pathogenic E. coli and expressed as a fusion protein with GST (glutathion S-transferase) in E. coli BL21 (DE3), in an attempt to harvest a large quantity of soluble HLT-B. The culture conditions, including the culture media used, temperature, pH and the presence of lactose as an inducer, were all optimized in order to obtain an increase in the expression of soluble GST-rHLT-B. The biological activity of the purified rHLT-B was assayed in a series of GM1-ELISA experiments. The findings of these trials indicated that the yield of soluble recombinant GST-rHLT-B could be increased by up to 3-fold, as compared with that seen prior to the optimization, and that lactose was a more efficient alternative inducer than IPTG. The production of rHLT-B, at 92% purity, reached an optimal level of 96 mg/l in a 3.7 L fermentor. The specific GM1 binding ability of the purified rHLT-B was determined to be almost identical to that of standard CTB.

The Association between Dairy Intake and Breast Cancer in Western and Asian Populations: A Systematic Review and Meta-Analysis

Jiajie Zang,Meihua Shen,Sufa Du,Tianwen Chen,Shurong Zou 한국유방암학회 2015 Journal of breast cancer Vol.18 No.4

Purpose: To date, studies investigating the association between dairy consumption and breast cancer in women have produced conflicting results. As diet is an important, modifiable factor affecting cancer development, the aim of this study was to examine the association between dairy consumption and breast cancer risk. Methods: PubMed, Embase, and Cochrane Library databases were searched with a priority for prospective cohort studies. Case-control studies were also considered in case of the absence of a cohort study. Results: We analyzed 22 prospective cohort studies (1,566,940 participants) and five case-control studies (33,372 participants). High and modest dairy consumption (>600 and 400–600 g/day, respectively) significantly reduced the risk of breast cancer compared with low dairy consumption (<400 g/day; risk ratio [RR], 0.90, 95% confidence interval [CI], 0.83–0.98, and RR, 0.94, 95% CI, 0.91–0.98, respectively). A significant linear relationship between dairy consumption and breast cancer risk was found on dose-response analysis. Subgroup analysis found that yogurt (RR, 0.91; 95% CI, 0.83–0.99) and low-fat dairy (RR, 0.85; 95% CI, 0.75–0.96) reduced the risk of breast cancer, while other dairy product types did not. A reduced risk was observed for people in the United States (RR, 0.91; 95% CI, 0.83–0.99) and in those followed for ≥10 years (RR, 0.90; 95% CI, 0.81–0.99). Additionally, the highest level of dairy consumption among Asians was associated with a reduced risk of breast cancer (odds ratio, 0.74; 95% CI, 0.62–0.88). Conclusion: Dairy consumption was inversely associated with the risk of developing breast cancer and this effect was dependent on the dose, dairy-type, and time.

Microstructure and Mechanical Properties of Squeeze Cast Al-5 Mg-3Zn-1Cu-1Si Alloy Along Cross Section

Zhongyang Li,Qudong Wang,Huaping Tang,Tianwen Liu,Chuan Lei,Haiyan Jiang,Wenjiang Ding 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.10

The variation of microstructure and mechanical properties along the cross section of squeeze cast Al-5Mg-3Zn-1Cu-1Sialloy is studied under both squeeze-cast and peak-aged condition (470 °C × 24 h + 125 °C × 24 h). For squeeze-cast alloy,along the depth direction, second dendrite arm space and the percentage of -Al increase significantly, while the volumefraction of T-Mg32(AlZnCu)49 and Mg2Siphase showed a dramatic decrease. The ultimate tensile strength of squeeze-castalloy slightly decreased from 357.04 MPa for the surface layer to 344.21 MPa for the central layer, yield strength droppedfrom 296.86 MPa to 241.03 MPa, but the elongation almost tripled from 1.42% to 3.78%. After peak aging, the ultimatetensile strength of surface layer and central layer reached 538.45 MPa and 504.03 MPa, yield strength reached 447.46 MPaand 442.65 MPa, and the elongation reached 5.23% and 3.97% respectively. Meanwhile the difference of ultimate tensilestrength and elongation was increased, but that of yield strength reduced after aging treatment. Precipitation strengtheningis the main strengthening mechanism while the improvement in ductility is due to the dissolution of T-Mg32(AlZnCu)49 andthe morphological change of eutectic Mg2Si.

Optimization and High-level Expression of a Functional GST-tagged rHLT-B in Escherichia coli and GM1 Binding Ability of Purified rHLT-B

Ma Xingyuan,Zheng Wenyun,Wang Tianwen,Wei Dongzhi,Ma Yushu The Microbiological Society of Korea 2006 The journal of microbiology Vol.44 No.3

The Escherichia coli heat-labile enterotoxin B subunit (HLT-B) is one of the most powerful mucosal immunogens and known mucosal adjuvants. However, the induction of high levels of HLT-B expression in E. coli has proven a difficult proposition. Therefore, in this study, the HLT-B gene was cloned from pathogenic E. coli and expressed as a fusion protein with GST (glutathion S-transferase) in E. coli BL2l (DE3), in an attempt to harvest a large quantity of soluble HLT-B. The culture conditions, including the culture media used, temperature, pH and the presence of lactose as an inducer, were all optimized in order to obtain an increase in the expression of soluble GST-rHLT-B. The biological activity of the purified rHLT-B was assayed in a series of GMI-ELISA experiments. The findings of these trials indicated that the yield of soluble recombinant GST-rHLT-B could be increased by up to 3-fold, as compared with that seen prior to the optimization, and that lactose was a more efficient alternative inducer than IPTG. The production of rHLT-B, at 92 % purity, reached an optimal level of 96 mg/l in a 3.7 L fermentor. The specific GM1 binding ability of the purified rHLT-B was determined to be almost identical to that of standard CTB.

Effects of boron source composition ratio on the microstructure and adsorption performance of hexagonal boron nitride prepared by template method

Zhang Ning,Liu Huan,Zhang Tianwen,Kan Hongmin,Wang Xiaoyang,Cui Xingyu 한양대학교 세라믹연구소 2016 Journal of Ceramic Processing Research Vol.17 No.3

The paper was prepared spherical hexagonal boron nitride with different microstructures under flowing ammoniaatmosphere. The effect of boron source component ratios (molar ratio of borax and boric acid) on the phase composition ofthe sample were studied: the work also explored the effect of boron source component ratio on the microstructure andadsorption performance of h-BN. Spherical hexagonal boron nitride had corresponding to shell structure, mesoporousstructure, and solid structure when the ratio of boron source components respectively was 1 : 0.5, 1 : 1, and 1 : 2. Between 1 : 1and 1:0.5, the former had an lower adsorptions at low relative pressures. On the contrary, the adsorption of former wouldincreased at higher relative pressures and reached up 276.02 cm3 g−1, and the maximum adsorption of the latter reached only228.20 cm3 g−1. Under any relative pressure, the adsorption capacity was the lowest when the boron source composition ratiowas 1 : 2.