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423 results on '"Feng, Zi-Ming"'

4. Three new flavonoids from the roots of Sophora tonkinensis

Author

Yan, Xiao-Yun, primary, Zhang, Rui, additional, Yang, Ya-Nan, additional, Feng, Zi-Ming, additional, Jiang, Jian-Shuang, additional, Yuan, Xiang, additional, Wang, Dong-Mei, additional, Wang, Guo-Cheng, additional, Zhang, Xu, additional, and Zhang, Pei-Cheng, additional

Published
2024
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10. Two new cucurbitane-type triterpenoid saponins from the fruit of Citrullus colocynthis.

Author

Liu, Si-Qi, Feng, Zi-Ming, Yuan, Xiang, Zhang, Xu, Yang, Ya-Nan, He, Jiang, Zhang, Pei-Cheng, and Jiang, Jian-Shuang

Subjects
*TRITERPENES, *CHINESE medicine, *MELONS, *HEPATOTOXICOLOGY, *NUCLEAR magnetic resonance spectroscopy, *RESEARCH funding, *SPECTROPHOTOMETERS, *PLANTS, *CELL lines, *MEDICINAL plants, *MOLECULAR structure, *MASS spectrometry, *BIOLOGICAL assay, *ACETAMINOPHEN
Abstract

Two new cucurbitane-type triterpenoid saponins, 2,20β,22β-trihydroxy-16α,23(R)-epoxycucurbita-1,5,24-triene-3,11-dione 2-O-β-D-glucopyranoside (1), 2,20β,22α-trihydroxy-16α,23(S)-epoxycucurbita-1,5,11,24-tetraene-3-one 2-O-β-D-glucopyranoside (2) were isolated from the fruit of Citrullus colocynthis (L.) Schrad. Their structures were elucidated by mass spectrometry, IR, 1D, and 2D NMR spectroscopy, etc. Besides, both of the compounds showed significant hepatoprotective activities at 10 μM against paracetamol-induced HepG2 cell damage. [ABSTRACT FROM AUTHOR]

Published
2024
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18. Dynamic Model and Analysis of a Sucker-rod Pump Injection-production System

Author

Jiang Minzheng, Zhang Deshi, Feng Zi-Ming, and Duan Tianyu

Subjects
dynamic model, injection-production system, Gibbs model, sucker-rod pump, Engineering (General). Civil engineering (General), TA1-2040
Abstract

Injection and production at the same oil well is an effective way to achieve stable production and control water-cut. A sucker-rod pump injection-production system is composed of a production pump, piston seal, injection pump, and so on. It separates oil and water down the well hole using gravity, then injects the water directly into the formation while the concentrated oil is brought to the surface. To explore the complex forces involved in the system, static and dynamic models of the injection pump, sealed piston and production pump are established from the bottom up based on the mechanical method, and a solution is established using the difference method. Finally, a dynamic simulation of the system is compiled in Visual Basic V6.0, and the correctness and practicality of the simulation are verified by field measurements.

Published
2019
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25. ANALYSIS OF PRACTICAL ABILITY IMPROVEMENT FOR TEACHERS BASED ON THE 'EXCELLENCE PLAN'

Author

Li Hong-Mei and Feng Zi-Ming

Subjects
engineering practice ability, excellent engineers, higher engineering education, professional teachers, Education (General), L7-991, Engineering (General). Civil engineering (General), TA1-2040
Abstract

The “excellence plan” is aimed at developing high quality engineering and technical talents who have a strong ability for innovation, can adapt to the development needs of society and can work out strategies for making the country stronger. At the same time, the “excellence plan” colleges are required to build a team which would include high level full-time and part-time teachers with engineering experience. This paper analyses the current situation of teachers’ ability for engineering practice and practical ability from the following points of view: bringing into play subjective initiative, interacting practical experience among teachers, adjusting the practical teaching link, training for teachers’ positions and training double-tutors with cooperation between schools and enterprises.

Published
2014

27. EXPLORATION AND PRACTICE OF SCHOOL-ENTERPRISE COOPERATION IN PRACTICAL EDUCATION BASED ON 'OUTSTANDING PROJECT'

Author

Li Hong-Mei, Han Dan, Feng Zi-Ming, and Li Qiang

Subjects
outstanding project, school - enterprise cooperation, innovative research, the ability to conduct engineering practice, Education (General), L7-991, Engineering (General). Civil engineering (General), TA1-2040
Abstract

There will be difficulties in moving forward the project for educating and cultivating outstanding engineers, therefore, based on the outstanding project, it’s crucial to come up with an efficient method to deal with the issues in the practice of school-enterprise cooperation engineering. This thesis is going to deliver the discussions in the following aspects: a. The forms and contents of how to build the school-enterprise cooperation practice; How do we conduct engineering practice; c. How do we make sure enough teachers and working places for engineering practice are provided; d. How do we guarantee the quality of engineering practice and build its related valuation system.

Published
2013

32. Development and Performance Research of New Small Displacement Pump with Solid Plunger and Non-coaxial Delivery Valve

Author

Feng Zi-Ming, Duan Wei-Bo, and Cui Wei

Subjects
Plunger, Materials science, General Engineering, Displacement (orthopedic surgery), Development (differential geometry), 02 engineering and technology, Mechanics, Coaxial, 010402 general chemistry, 021001 nanoscience & nanotechnology, 0210 nano-technology, 01 natural sciences, 0104 chemical sciences
Abstract

Background: After the oilfield development coming into the middle and later periods, many oil wells only had liquid production less than 5m3 per day, therefore the present sucker-rod pumps didn’t satisfy the need for oilfield production. We revised all patents relating to small displacement pump and didn’t found any suitable pump for low production well. A new type of pump with small diameter was needed to design for solving the unbalance between the production and feed in lower production wells. Objective: o resolve the problems of supply and production imbalance of the low producing well, low pump efficiency and low system efficiency, a low displacement pump with non-coaxial delivery valve had been designed. Methods: This type pump adopted a solid plunger, and its delivery valve was not coaxial with the pump axial that would enhance its structural strength and been useful to reduce the partial flow loss of oil flowing through the static pump valve. At the down dead point of pump plunger, the delivery valve was located at the top of the pump chamber that was to the benefit of discharge of the gas and the oil from the pump chamber. The uneven distribution of the delivery hole was suitable for the wellhead diameter of the traditional oil wells. Results: The delivery valve was non-coaxial with the plunger that would decrease the flow loss through the passage and increase the pump efficiency. At the down-dead point, the plunger entered the extension nipple, and the delivery valve was located up the end of the solid plunger that promoted the remnant gas flowing out of the pump cylinder and decreased the effect of gas on the pump efficiency. Conclusion: As to this low displacement pump, we suggested: The suitable stroke was 2-3m; the stroke frequency was less than 3min-1. A reasonable range of submersible depth for low production well was 200-300m. It was used in the gas content well lower than 20%, else used the gas anchor firstly. The low displacement pump with non-coaxial delivery valve and solid plunger (NLDP) can improve the pump efficiency and reduce the polish rod load. At the same time, this NLDP provides new equipment for the production of the low oil well and improves the artificial lift design theory.

Published
2019

39. Evaluation and Improvement of Pumping Well Operating Conditions in an Oil Field Block Based on Grey Correlation Analysis

Author

Feng*, Zi-Ming, Huang, Jincheng, Cui, Wei, Chen, Yong, Li, Chunhong, Feng*, Zi-Ming, Huang, Jincheng, Cui, Wei, Chen, Yong, and Li, Chunhong

Abstract

The "Oil and Gas Water Well Production Data Management System Database" provides great assistance for oilfield production, monitoring, and management. However, due to the harsh conditions of oil field wells and the lack of some test data, traditional management methods are no longer suitable for present condition. At the same time, optimization analysis for a single oil well has a high cost and low efficiency, and it is difficult to achieve the modern management goal of large-scale pumping well groups. In this paper, the grey correlation method is used to analyze the direct correlation between the influencing factors and the system efficiency, surface equipment driving efficiency, and wellbore lifting efficiency, and the improvement method against factors with strong correlation is prioritized. A multi-node evaluation index system for pumping well systems and corresponding improvement methods were constructed, and evaluation software was compiled. This technology considers the running condition of the pumping unit in one oil field block, and selects the oil wells to be improved according to the evaluation index, and puts forward the targeted improvement methods according to the common problems of the oil well. This paper provides a set of reliable technical methods for the efficient management of the oil well in the oil field block.

Published
2021

40. Neosophoflavonoids A–C, A class of highly oxidized hybrid flavonoids from Sophora flavescenswith antidiabetic effects

Author

Zhang, Xu, Li, Jiang, Lu, Kai-Zhou, Yang, Ya-Nan, Jiang, Jian-Shuang, Yuan, Xiang, Feng, Zi-Ming, Ye, Fei, and Zhang, Pei-Cheng

Abstract

Three highly oxidized hybrid flavonoids neosophoflavonoids A–C (1, 2a, and 2b) were isolated from the roots of Sophora flavescens. Neosophoflavonoid A possesses a unique highly oxidized heptacyclic 6/6/6/6/6/6/5 system. Neosophoflavonoids B and C are isomers and share the same highly oxidized hexacyclic 6/6/6/6/6/6 systems. Their planar structures were elucidated from 1D/2D nuclear magnetic resonance (NMR), ultraviolet spectroscopy (UV), infrared spectroscopy (IR), and high resolution electrospray ionization mass spectroscopy (HRESIMS) data. Their absolute configurations were determined by thorough GIAO 13C NMR (DP4+) calculation protocol and electronic circular dichroism (ECD) calculation method. The plausible biosynthetic routes for the compounds were also proposed. All compounds exhibited significant protein tyrosine phosphatase-1B (PTP1B) inhibitory activity with half maximal inhibitory concentration (IC50) values 3.94 ± 0.01, 0.38 ± 0.13, and 0.70 ± 0.01 μmol/L, respectively. In addition, compared to a positive control fenofibrate (Feno) at 20 μmol/L, compounds 2aand 2bexhibited stronger inhibitory effects on lipid accumulation in the oleic acid (OA)-induced cell model at 5 and 10 μmol/L.

Published
2024
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