Simulation study of new directional drilling PDC bit used in coal mine

Rongjun Sun,Pei Ju,Zhijun Shi 한국자원공학회 2017 Geosystem engineering Vol.20 No.3

During directional drilling, when drilling in hard and multi-interbedded formation, the ordinary flat-bottomed PDC bit wears seriously, in order to solve this problem, a new type of directional drilling PDC bit (straight angle drag PDC bit) is developed, and numerical simulation method is used to analyze the working characteristics of straight angle drag PDC bit. Simulation results show that, comparing with the ordinary flat-bottomed PDC bit, axial force needed by straight angle drag PDC bit reduces by up to 36%, and rock breaking efficiency increases nearly 50%. Also, Φ96 mm straight angle drag PDC bit is produced and field test is carried out; field test results show that: comparing with flat-bottomed PDC bit, bit life expectancy of straight angle drag PDC bit increases more than three times, and rock breaking efficiency increases about two times. So, when drilling in hard and multi-interbedded formation in the process of directional drilling, straight angle drag PDC bit helps to improve bit life and rock breaking efficiency and finally reduces drilling cost.

Sequence analysis and expression of the calmodulin gene, MCaM-3, in mulberry (Morus L.)

Rongjun Fang,Dongqing Hu,Yinghua Zhang,Long Li,Weiguo Zhao,Li Liu,Jialin Cheng,Jinliang Qi,Yonghua Yang 한국유전학회 2011 Genes & Genomics Vol.33 No.2

A full-length cDNA sequence encoding CaM from mulberry,which we designated MCaM-3 (GenBank accession No:GQ303247), was cloned based on mulberry expressed sequence tags(ESTs). Sequence analysis showed that MCaM-3is 951 base pairs in length, encoding 149 amino acids with a predicted molecular weight of 16.85 kD and an isoelectric point of 3.95. Online SMART analysis showed that the MCaM-3 protein has four EFh functional domains, which can bind calcium. The expression level of MCaM-3at different developmental stages in mulberry leaves and flowers and in different tissues was investigated. The results showed that MCaM-3 transcripts are most abundantly expressed in mature tissues, such as mature female flowers and climax leaves, and the expression level of the mRNA could be increased significantly under low temperature, drought, and salt stress conditions compared to the normal growth environment. This research will help us understand the resistance mechanism of functional genes in mulberry.

Differential global gene expression changes in response to low nitrogen stress in two maize inbred lines with contrasting low nitrogen tolerance

Rongjun Chen,Xun Wu,Mengliang Tian,Yubi Huang 한국유전학회 2011 Genes & Genomics Vol.33 No.5

The global gene expression changes in response to low nitrogen stress in leaf tissues of two maize inbred lines(Mo17 and Hz4) with contrasting low nitrogen tolerance was analyzed using the Affymetrix maize genome array. Our results showed 887 genes involved in a variety of biological processes were responsive to low nitrogen treatment in Mo17, out of which 384 were up-regulated and 503 were down-regulated. In Hz4the expression of 1108 genes was changed, of which 696 were up-regulated and 412 genes were down-regulated. The gene expression profiles also revealed 1799 genes differentially expressed (910 and 889 genes with higher level of expression in Hz4 and Mo17, respectively) between the two lines under low nitrogen conditions. These results explain at the transcript level why Mo17 is more sensitive than Hz4 under low nitrogen stress. In addition to previously reported nitrogen response genes (nitrate transporter, nitrite reductase, nitrate reductase,ferredoxin) we found many new nitrogen response genes (early light-inducible protein,uroporphyrinogen methyltransferas e,phosphoenolpyruvate carboxylase, tonoplast intrinsic protein,sesquiterpene cyclase). Our results not only provide new insights on the molecular mechanisms of nitrogen stress, but also serve as a valuable resource to researchers who aim to improve the efficiency of maize nitrogen use.

Genome-wide analysis and environmental response profiling of SOT family genes in rice (Oryza sativa)

Rongjun Chen,Yunyun Jiang,Jiali Dong,Xin Zhang,Hongbo Xiao,Zhengjun Xu,Xiaoling Gao 한국유전학회 2012 Genes & Genomics Vol.34 No.5

Sulphotransferase (SOT) catalyses the transfer of a sulphonate group from 3'-phosphoadenosine 5'-phosphosulphate (PAPS)to an appropriate hydroxyl group of various substrates with the parallel formation of 3'-phosphoadenosine 5'-phosphate (PAP). Although several SOTs have been identified and characterized in mammalian, their role in plant is still unclear. In this study, we report genome-wide comprehensive expression analysis of 35 putative SOT genes in rice. The 35 OsSOTs were tandemly arranged into six clusters. The phylogenetic analysis showed that there were 7 subfamilies of OsSOTs and 11 putatively conserved motifs. Six OsSOTs might be pseudogenes,25 have the two motifs which were involved in PAPS binding regions I and IV. Microarray data indicated that all the OsSOTs were expressed almost at the same level but with different patterns: most OsSOTs were expressed exclusively in stigma and ovary and induced by IAA and BAP, several genes were induced by tZ and DMSO and 11 OsSOTs were response to abiotic stress. Further analysis showed that these 11 genes contained cis-regulatory elements responding to abiotic stresses.

Sampled-data Fuzzy Control of Two-wheel Inverted Pendulums Based on Passivity Theory

Rongjun Liu,Junfeng Wu,Dan Wang 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.5

In this paper, an aperiodically sampled-data control scheme is detailed for the two-wheel inverted pendulum using Takagi-Sugeno (T-S) fuzzy models. The passivity theory is applied in the presence of the disturbances in the actuator channel. A two-rule fuzzy model is utilized to represent the two-wheel inverted pendulum. By using the pendulum angle as the antecedent variable of the fuzzy rule, a passive sampled-data controller is established using the pendulum inclination angle and the mean value of the rim motors’ rotary angles. A Lyapunov-like function based on the two fuzzy rules is constructed to develop criteria of passivity, by the utilization of very-strict passivity in terms of the pendulum angle. Then a solution to the gains of sampled-data controller is synthesized to ensure the very-strict passivity of the pendulum system. By the illustrative examples, the effectiveness of the variable-sampling control scheme is validated for the two-wheel inverted pendulum.

Homogeneous preparation of polyamidoamine grafted silica gels and their adsorption properties as Au3+ adsorbents

Rongjun Qu,Xilu Ma,Minghua Wang,Changmei Sun,Xiaomei Sun,Shaoying Sun,Ying Zhang,Ping Yin 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.6

A series of low generation dendrimer polyamidoamine grafted silica gels (named SiO2-G1.0, SiO2-G2.0,SiO2-G3.0) were synthesized via the homogeneous route. The new materials were characterized byscanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), thermal analysis,pore and surface area analysis, X-ray diffraction analysis (XRD) and elemental analysis. The adsorptionproperties of the three products for Au3+ were studied by batch methods. The adsorbents prepared viathe homogeneous route showed higher adsorption capacities than those via the heterogeneous route. The maximum adsorption capacities for the three could reach up to 1.48, 2.45, and 2.21 mmol g-1,respectively.

In vitro Inhibition of Fungal Root-Rot Pathogens of Panax notoginseng by Rhizobacteria

Rongjun Guo,Xingzhong Liu,Shidong Li,Zuoqing Miao 한국식물병리학회 2009 Plant Pathology Journal Vol.25 No.1

The rhizobacteria of Panax notoginseng were isolated from six sites in Yanshan, Maguan and Wenshan Counties, Yunnan Province of China, and their antagonistic activity against P. notoginseng root-rot fungal pathogens was determined. Of the 574 rhizobacteria isolated, 5.8% isolates were antagonistic in vitro to at least one of the five pathogens, Cylindrocarpon didynum, Fusarium solani, Phytophthora cactorum, Phoma herbarum, and Rhizoctonia solani. The number of rhizo bacteria and the number that inhibited fungi differed depending on sampling sites and isolation methods. Rhizobacteria isolated from the site in Yanshan and Maguan showed more antagonistic effect than them in Wenshan. Heat treatment of rhizosphere soil at 80oC for 20 min scaled the antagonists up to 14.0%. Antagonistic bacteria in the roots proportioned 3.9% of the total isolates. The most antagonistic isolates 79-9 and 81-4 are Bacillus subtilis based on their 16S rDNA sequence and biochemical and physiological characteristics. Identification and evaluation of antagonistic bacteria against P. notoginseng root-rot pathogens in the main planting areas improved our understanding of their distribution in rhizosphere soil. Furthermore these results indicated that the interactions between biocontrol agent and soil microbes should be seriously considered for the successful survival and biocontrol efficacy of the agents in soil.

Genome-wide analysis and environmental response profiling of dirigent family genes in rice (Oryza sativa)

Rongjun Chen,Yongrong Liao,Shengbin Liu,Yunyun Jiang,Changqiong Hu,Xuewei Zhang,Xufeng Cao,Zhengjun Xu,Xiaoling Gao,Lihua Li,Jianqing Zhu 한국유전학회 2017 Genes & Genomics Vol.39 No.1

Dirigent (DIR) and DIR-like family genes were involved in lignification or in the response to pathogen infection and abiotic stress in plants. Little is known to us about how rice DIR genes respond to adverse conditions. In this study, we reported genome-wide analysis of 49 DIR or DIR-likes genes in rice. The 49 OsDIRs or OsDIR-likes were tandem arranged into ten clusters. The phylogenetic analysis indicated that the 49 rice DIR and DIR-like genes cluster into five distinct subfamilies, DIR-a and four DIRlike subfamilies (DIR-b/d, and DIR-g, DIR-c, DIR-e). Meta-analysis of microarray gene expression datas indicated that all the OsDIRs or OsDIR-likes were expressed almost at the same level but with different patterns: most OsDIRs or OsDIR-likes were expressed exclusively in stigma and ovary and were induced by IAA and BAP; several genes were induced by trans-zeatin (tZ) and DMSO; 23 OsDIRs or OsDIR-likes were responded to abiotic stress. Our analysis also showed that most of these genes could respond to abiotic stresses, which contained cis-regulatory elements. The present study will provide a useful reference for further functional analysis of the DIR genes in rice.

In vitro Inhibition of Fungal Root-Rot Pathogens of Panax notoginseng by Rhizobacteria

Guo, Rongjun,Liu, Xingzhong,Li, Shidong,Miao, Zuoqing The Korean Society of Plant Pathology 2009 Plant Pathology Journal Vol.25 No.1

The rhizobacteria of Panax notoginseng were isolated from six sites in Yanshan, Maguan and Wenshan Counties, Yunnan Province of China, and their antagonistic activity against P. notoginseng root-rot fungal pathogens was determined. Of the 574 rhizobacteria isolated, 5.8% isolates were antagonistic in vitro to at least one of the five pathogens, Cylindrocarpon didynum, Fusarium solani, Phytophthora cactorum, Phoma herbarum, and Rhizoctonia solani. The number of rhizo bacteria and the number that inhibited fungi differed depending on sampling sites and isolation methods. Rhizobacteria isolated from the site in Yanshan and Maguan showed more antagonistic effect than them in Wenshan. Heat treatment of rhizosphere soil at $80^{\circ}C$ for 20 min scaled the antagonists up to 14.0%. Antagonistic bacteria in the roots proportioned 3.9% of the total isolates. The most antagonistic isolates 79-9 and 81-4 are Bacillus subtilis based on their 168 rDNA sequence and biochemical and physiological characteristics. Identification and evaluation of antagonistic bacteria against P. notoginseng root-rot pathogens in the main planting areas improved our understanding of their distribution in rhizosphere soil. Furthermore these results indicated that the interactions between biocontrol agent and soil microbes should be seriously considered for the successful survival and biocontrol efficacy of the agents in soil.

High efficient adsorption of gold ions onto the novel functional composite silica microspheres encapsulated by organophosphonated polystyrene

Ping Yin,Rongjun Qu,Mingyu Xu,Wei Liu,Xiguang Liu,Qiang Xu 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.2

The novel functional composite silica microspheres encapsulated by organophosphonated polystyrene(SG–PS–N–P) has been successfully synthesized. SG–PS–N–P was employed to adsorb Au(III) fromsimulated wastewater, and it exhibited excellent performance, and the maximum adsorption capacitywas 980.39 mg/g at 35 ℃. The adsorption process optimization was performed using response surfacemethodology (RSM), and the analysis of variance (ANOVA) of the quadratic model demonstrated that themodel was highly significant. Moreover, the regeneration capacities of SG–PS–N–P were investigated,and it has been found that the adsorption capability remains high after several cycles of adsorption–desorption.