Biotechnology Research in Shanghai Jiao Tong University

Jian-Jiang Zhong 한국생물공학회 2011 한국생물공학회 학술대회 Vol.2011 No.10

Efficient Elicitation of Ginsenoside Biosynthesis in Cell Cultures of Panax notoginseng by Using Self-chemically-synthesized Jasmonates

Jian-Jiang Zhong,Wei Wang,Zhen-Jiang Zhao,Yufang Xu,Xuhong Qian 한국생물공학회 2005 Biotechnology and Bioprocess Engineering Vol.10 No.2

A series of fluorine and hydroxyl containing jasmonate derivatives, which were chemically synthesized in our institute, were investigated for their effects on the biosynthesis and heterogeneity of ginsenosides in suspension cultures of Panax notoginseng cells. Compared to the control (without addition of elicitors), 100 M of each of the jasmonate was added on day 4 to the suspension cultures of P. notoginseng cells. It was observed that, jasmonates greatly enhanced the ginsenoside content and the ratio of Rb group to Rg group (i.e. (Rb1 + Rd)/(Rg1 + Re)) in the P. notoginseng cells. Some of the synthetic jasmonates, such as pentafluoropropyl jasmonate (PFPJA), 2-hydroxyethyl jasmonate (HEJA) and 2-hydroxye-thoxyethyl jasmonate (HEEJA), could promote the ginsenoside content to 2.55 0.11, 3.65 0.13 and 2.94 0.06 mg/100 mg DW, respectively, compared to that of 0.64 0.06 mg/100 mg DW for the control and 2.17 0.04 mg/100 mg DW by the commercially available methyl jasmonate (MJA); and they could change the respective Rb:Rg ratio to 1.60 0.04, 1.87 0.01 and 1.56 0.05, compared to that of 0.47 0.01 for the control and 1.42 0.06 by MJA. The results suggest that suitable esterification of MJA with fluorine or hydroxyl group could increase the elicitation activity to induce plant secondary metabolism. The information obtained from this study is useful for hyper-production of heterogeneous products by plant cell cultures.

Secondary Metabolites from Medicinal Higher Fungi

Jian-Jiang Zhong,Jian-Hui Xiao 한국생물공학회 2008 한국생물공학회 학술대회 Vol.2008 No.4

Progressive Collapse of Steel High-Rise Buildings Exposed to Fire: Current State of Research

Jiang, Jian,Li, Guo-Qiang Council on Tall Building and Urban Habitat Korea 2018 International journal of high-rise buildings Vol.7 No.4

This paper presents a review on progressive collapse mechanism of steel framed buildings exposed to fire. The influence of load ratios, strength of structural members (beam, column, slab, connection), fire scenarios, bracing systems, fire protections on the collapse mode and collapse time of structures is comprehensively reviewed. It is found that the key influencing factors include load ratio, fire scenario, bracing layout and fire protection. The application of strong beams, high load ratios, multi-compartment fires will lead to global downward collapse which is undesirable. The catenary action in beams and tensile membrane action in slabs contribute to the enhancement of structural collapse resistance, leading to a ductile collapse mechanism. It is recommended to increase the reinforcement ratio in the sagging and hogging region of slabs to not only enhance the tensile membrane action in the slab, but to prevent the failure of beam-to-column connections. It is also found that a frame may collapse in the cooling phase of compartment fires or under travelling fires. This is because that the steel members may experience maximum temperatures and maximum displacements under these two fire scenarios. An edge bay fire is more prone to induce the collapse of structures than a central bay fire. The progressive collapse of buildings can be effectively prevented by using bracing systems and fire protections. A combination of horizontal and vertical bracing systems as well as increasing the strength and stiffness of bracing members is recommended to enhance the collapse resistance. A protected frame dose not collapse immediately after the local failure but experiences a relatively long withstanding period of at least 60 mins. It is suggested to use three-dimensional models for accurate predictions of whether, when and how a structure collapses under various fire scenarios.

Simulating the Response of a 10-Storey Steel-Framed Building under Spreading Multi-Compartment Fires

Jiang, Jian,Zhang, Chao Council on Tall Building and Urban Habitat Korea 2018 International journal of high-rise buildings Vol.7 No.4

This paper presents a numerical investigation on the structural response of a multi-story building subjected to spreading multi-compartment fires. A recently proposed simple fire model has been used to simulate two spreading multi-compartment fire scenarios in a 10-story steel-framed office building. By assuming simple temperature rising and distribution profiles in the fire exposed structural components (steel beams, steel column and concrete slabs), finite element simulations using a three-dimensional structural model has been carried out to study the failure behavior of the whole structure in two multi-compartment fire conditions and also in a standard fire condition. The structure survived the standard fire but failed in the multi-compartment fire. Whilst more accurate fire models and heat transfer models are needed to better predict the behaviors of structures in realistic fires, the current study based on very simple models has demonstrated the importance and necessity of considering spreadingmulti-compartment fires in fire resistance design of multi-story buildings.

A GENERALIZATION OF LOCAL SYMMETRIC AND SKEW-SYMMETRIC SPLITTING ITERATION METHODS FOR GENERALIZED SADDLE POINT PROBLEMS

Jian-Lei Li,Dang Luo,Zhi-Jiang Zhang 한국전산응용수학회 2011 Journal of applied mathematics & informatics Vol.29 No.5

In this paper, we further investigate the local Hermitian and skew-Hermitian splitting (LHSS) iteration method and the modified LHSS (MLHSS) iteration method for solving generalized nonsymmetric saddle point problems with nonzero (2,2) blocks. When A is non-symmetric positive definite, the convergence conditions are obtained, which generalize some results of Jiang and Cao [M.-Q. Jiang and Y. Cao, On local Hermitian and Skew-Hermitian splitting iteration methods for generalized saddle point problems, J. Comput. Appl. Math., 2009(231): 973-982] for the generalized saddle point problems to generalized nonsymmetric saddle point problems with nonzero (2,2) blocks. Numerical experiments show the effectiveness of the iterative methods.

Production of antitumor ganoderic acids from mushroom fermentation

Jian-Jiang Zhong,Jun-Wei Xu,Cui-Xia Liang 한국생물공학회 2009 한국생물공학회 학술대회 Vol.2009 No.10

Studies on Validamycin A Fermentation : Making the Old New

Jian-Jiang Zhong,Yueqiao Liao,Zhen-Hua Wei 한국생물공학회 2009 한국생물공학회 학술대회 Vol.2009 No.4

Review on Quantitative Measures of Robustness for Building Structures Against Disproportionate Collapse

Jiang, Jian,Zhang, Qijie,Li, Liulian,Chen, Wei,Ye, Jihong,Li, Guo-Qiang Council on Tall Building and Urban Habitat Korea 2020 International journal of high-rise buildings Vol.9 No.2

Disproportionate collapse triggered by local structural failure may cause huge casualties and economic losses, being one of the most critical civil engineering incidents. It is generally recognized that ensuring robustness of a structure, defined as its insensitivity to local failure, is the most acceptable and effective method to arrest disproportionate collapse. To date, the concept of robustness in its definition and quantification is still an issue of controversy. This paper presents a detailed review on about 50 quantitative measures of robustness for building structures, being classified into structural attribute-based and structural performance-based measures (deterministic and probabilistic). The definition of robustness is first described and distinguished from that of collapse resistance, vulnerability and redundancy. The review shows that deterministic measures predominate in quantifying structural robustness by comparing the structural responses of an intact and damaged structure. The attribute-based measures based on structural topology and stiffness are only applicable to elastic state of simple structural forms while the probabilistic measures receive growing interest by accounting for uncertainties in abnormal events, local failure, structural system and failure-induced consequences, which can be used for decision-making tools. There is still a lack of generalized quantifications of robustness, which should be derived based on the definition and design objectives and on the response of a structure to local damage as well as the associated consequences of collapse. Critical issues and recommendations for future design and research on quantification of robustness are provided from the views of column removal scenarios, types of structures, regularity of structural layouts, collapse modes, numerical methods, multiple hazards, degrees of robustness, partial damage of components, acceptable design criteria.

Progressive collapse of steel-framed gravity buildings under parametric fires

Jian Jiang,Wenyu Cai,Guo-Qiang Li,Wei Chen,Jihong Ye 국제구조공학회 2020 Steel and Composite Structures, An International J Vol.36 No.4

This paper investigates the progressive collapse behavior of 3D steel-framed gravity buildings under fires with a cooling phase. The effect of fire protections and bracing systems on whether, how, and when a gravity building collapses is studied. It is found that whether a building collapses or not depends on the duration of the heating phase, and it may withstand a “short-hot” fire, but collapses under a mild fire or a “long-cool” fire. The collapse time can be conservatively determined by the time when the temperature of steel columns reaches a critical temperature of 550 °C. It is also found that the application of a higher level of fire protection may prevent the collapse of a building, but may also lead to its collapse in the cooling phase due to the delayed temperature increment in the heated members. The tensile membrane action in a heated slab can be resisted by a tensile ring around its perimeter or by tensile yielding lines extended to the edge of the frame. It is recommended for practical design that hat bracing systems should be arranged on the whole top floor, and a combination of perimeter and internal vertical bracing systems be used to mitigate the fire-induced collapse of gravity buildings. It is also suggested that beam-to-column connections should be designed to resist high tensile forces (up to yielding force) during the cooling phase of a fire.