Running-in performance of 7075 aluminum alloy strengthened by burnishing technology

Cong Ding,Shiqing Feng,Zhizhao Qiao,Zhenyu Zhou,Zhongyu Piao 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.5

A 2D ultrasonic burnishing technology was employed to strengthen 7075 aluminum alloy. The running-in experiments for original and burnished samples were implemented, and the running-in performance was explored qualitatively and quantitatively. The results show that the worn surface of an original sample exhibited the peelings, scratches, and abrasive particles, yet the wear form of a burnished sample was relatively single, mainly with scratches. The quantitative parameter “maximum distance between phase points d max ” was calculated. During the friction and wear process, the d max of friction coefficient signal displayed the variation of first decreasing and then stabilizing, which was consistent with the running-in and steadystate stages of the friction system. Compared with the original sample, the burnished sample had a less d max , which indicated that the phase trajectory had a more convergence, and the friction system had a better stability. This study can guide surface strengthening and running-in performance analysis.

Preliminary Correlation Between Warm Needling Treatment for Knee Osteoarthritis of Deficiency-Cold Syndrome and Metabolic Functional Genes and Pathways

Conge Tan,Weijun Ding,Wenzhe Feng,Jianguo Wang,Miqu Wang 사단법인약침학회 2010 Journal of Acupuncture & Meridian Studies Vol.3 No.3

The warm needling technique used in traditional Chinese medicine has been shown to be effective in the treatment and prevention of knee osteoarthritis (OA), but the biological mechanisms behind this action have not been well explored. This study investigated the molecular mechanisms behind warm needling using cDNA microarray technology, thus providing further scientific evidence for its efficacy. Ten patients with knee OA of deficiency-cold syndrome were selected for 2 weeks of warm needling treatment. This treatment involved stimulating the selected acupoints using needles with a burning moxa stick on their handle for 40 minutes per session. Pain intensity and accumulated clinical scores of deficiency-cold syndrome were assessed pretreatment and posttreatment using a 40-factor questionnaire of OA with deficiency-cold syndrome. Four patients with the best therapeutic efficacy were selected for cDNA microarray testing. Among the four patients, 41, 246,57 and 70 differentially expressed genes were obtained, with more than 50% of these differentially expressed genes functionally linked to primary, cellular and energy metabolism pathways. This work demonstrates that the molecular mechanism behind warm needling treatment may be associated with the regulation of metabolism-related genes and pathways.

Recursive Chaotic Desynchronized Fingerprint for Large Scale Distribution Using Social Network Analysis

Cong-huan Ye,Zeng-gang Xiong,Yao-Ming Ding,Xueming Zhang,Guangwei Wang,Fang Xu 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.7

Average collusion attack is a very effective attack for digital fingerprinting system. Moreover, the commercial value of the colluded content is often time-sensitive. The more profit the colluder will make from it when the colluded copy is distributed earlier. This paper presents a new collusion-resilience approach with recursive chaotic desynchronization and social network. It has processed chaotic transformations due to random image grid based on chaos. The experimental results show that collusion even with only two copies results in degradation of the image metric, even if those traitors try to resynchronization using image registration technology. However, it will take expensive computational cost to do that, and the visual quality is degraded expensively with the increase of the number of fingerprinted copies.

A Secure Fingerprinted Multimedia Distribution Using Social Network Analysis

Cong-huan Ye,Zeng-gang Xiong,Yao-ming Ding,Xueming Zhang,Guangwei Wang,Fang Xu 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.4

Collusion attack is a very effective attack for digital fingerprinting system. In order to remove or attenuate the fingerprint information hidden in fingerprinted content, a number of users produce a new colluded copy through their own fingerprinted copies. In this paper, we address a novel collusion-resisting desynchronization fingerprinting approach using social network analysis. The novelty of this paper is that collusion attack occurred in a multimedia social network community with high probability. Different from all existing works, with desynchronization model constructed upon social network, the original image is desynchronized to get many similar copies which are different from each other, and then they are assigned and distributed to subscribers according to social network analysis. Theory analysis shows that the presented desynchronization distribution method has significantly better performance than those existing distribution schemes. The experimental results also show that the average colluded images even with only two desynchronized copies have poor visual quality. And the visual quality of colluded images does not improve apparently with the increase of the number of copies.

Expression Characteristics of Proteins of the Insulin-like Growth Factor Axis in Non-small Cell Lung Cancer Patients with Preexisting Type 2 Diabetes Mellitus

Ding, Jing,Tang, Jie,Chen, Xin,Men, Hai-Tao,Luo, Wu-Xia,Du, Yang,Ge, Jun,Li, Cong,Chen, Ye,Cheng, Ke,Qiu, Meng,Liu, Ji-Yan Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.10

Background: Preexisting type 2 diabetes mellitus (T2DM) affects the prognosis and mortality of patients with some cancers. Insulin like growth factor (IGF) and insulin receptor (IR) signaling axes play important roles in both cancer and diabetes development. We aimed to explore the expression characteristics of proteins in IGF/IR axis in non-small cell lung cancer (NSCLC) cases with preexisting T2DM. Methods: Fifty-five NSCLC patients with preexisting T2DM were retrospectively included and matched by 55 NSCLC without diabetes at a 1:1 ratio. The expression of proteins in IGF/IR axis was detected by immunohistochemical staining. Clinicopathological data were collected to analyze their relationship with the protein expression. Results: Both IGF 1 receptor (IGF-1R) and insulin receptor substrate 2 (IRS-2) showed higher expression in the NSCLC with T2DM group, compared with those without T2DM. The high expression of IGF-1R and IRS-2 were found to be negatively associated with lymph node metastases and T staging in the T2DM group, respectively, and IRS-2 expression was also found more in the subgroup whose T2DM duration was more than 4 years. No difference was detected in the expression of IRS-1, IGF-1, IGF-2, IGFBP3, IR and mTOR between groups with or without T2DM. Conclusion: Our study found higher expression of IGF-1R and IRS-2 proteins in NSCLC patients with preexisting T2DM, and that there was an association with early stage NSCLC, which suggested that IGF signaling may play an important early event in development of NSCLC associated with diabetes.

Cyclic CO2 capture characteristics of a pellet derived from sol-gel CaO powder with Ca12Al14O33 support

Cong Luo,Ying Zheng,Yongqing Xu,Haoran Ding,Chuguang Zheng,Changlei Qin,Bo Feng 한국화학공학회 2015 Korean Journal of Chemical Engineering Vol.32 No.5

A novel calcium-based pellet was prepared by extrusion of sol-gel CaO powder and cement with high aluminum- based content. Limestone was used for comparison. The cyclic CO2 capture performance and carbonation kinetics of the sorbents were investigated in a thermogravimetric analyzer (TGA). The changes in phase and microstructure were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Brunauer Emmet Teller (BET) surface area, respectively. The results indicate that the pellet consisted of CaO and Ca12Al14O33 after initial calcination. Limestone reactivity decreased dramatically with the increase in the cycle number, whereas the pellet showed a relatively stable cyclic CO2 capture performance with high reactivity. The CO2 capture capacity of the pellet achieved 0.43 g CO2/g sorbent after 50 cycles at 650 oC and 850 oC for carbonation and calcination, respectively. Moreover, the pellet obtained fast carbonation rates with slight decay after multiple cycles. The porous microstructure of the pellet contributed to the high reactivity of the sorbent during high temperature reactions, and the support material of Ca12Al14O33, enhanced the cyclic durability of the calcium-based sorbents.

Enhanced cyclic stability of CO_2 adsorption capacity of CaO-based sorbents using La_2O_3 or Ca_12Al_14O_33 as additives

Cong Luo,Ying Zheng,Ning Ding,Chuguang Zheng 한국화학공학회 2011 Korean Journal of Chemical Engineering Vol.28 No.4

To improve the stability of CaO adsorption capacity for CO_2 capture during multiple carbonation/calcination cycles, modified CaO-based sorbents were synthesized by sol-gel-combustion-synthesis (SGCS) method and wet physical mixing method, respectively, to overcome the problem of loss-in-capacity of CaO-based sorbents. The cyclic CaO adsorption capacity of the sorbents as well as the effect of the addition of La_2O_3 or Ca_12Al_14O_33 was investigated in a fixed-bed reactor. The transient phase change and microstructure were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (FSEM), respectively. The experimental results indicate that La_2O_3 played an active role in the carbonation/calcination reactions. When the sorbents were made by wet physical mixing method,CaO/Ca_12Al_14O_33 was much better than CaO/La_2O_3 in cyclic CO_2 capture performance. When the sorbents were made by SGCS method, the synthetic CaO/La_2O_3 sorbent provided the best performance of a carbonation conversion of up to 93% and an adsorption capacity of up to 0.58 g-CO_2/g-sorbent after 11 cycles.

Natronorubrum halophilum sp. nov. isolated from two inland salt lakes

Cong-Qi Tao,Yi Ding,Yang-Jie Zhao,Heng-Lin Cui 한국미생물학회 2020 The journal of microbiology Vol.58 No.2

Two halophilic archaeal strains, SHR37T and NEN6, were isolated from salt lakes located in the Tibet and Xinjiang regions of China. The two strains were found to form a single cluster (99.9% and 99.3% similarity, respectively) separating them from the six current members of Natronorubrum (94.7– 96.9% and 86.1–90.8% similarity, respectively) on the basis of the 16S rRNA and rpoB gene sequence similarities and phylogenetic analysis. Diverse phenotypic characteristics differentiate strains SHR37T and NEN6 from current Natronorubrum members. Their polar lipids are C20C20 and C20C25 glycerol diether derivatives of PG, PGP-Me, and a major glycolipid chromatographically identical to disulfated mannosyl glucosyl diether (S2-DGD). Four minor unidentified glycolipids are also present. The OrthoANI and in silico DDH values of the two strains were 97.3% and 76.1%, respectively, which were much higher than the threshold values proposed as a species boundary (ANI 95–96% and in silico DDH 70%), which revealed that the two strains represent one species; the two values (ANI 79.0–81.9% and in silico DDH 23.5– 25.7%) of the strains examined in this study and the current members of Natronorubrum are much lower than the recommended threshold values, suggesting that strains SHR37T and NEN6 represent a genomically different species of Natronorubrum. These results showed that strains SHR37T (= CGMCC 1.15233T = JCM 30845T) and NEN6 (= CGMCC 1.17161) represent a novel species of Natronorubrum, for which the name Natronorubrum halophilum sp. nov. is proposed.

Effect of hybrid fibers on flexural performance of reinforced SCC symmetric inclination beams

Cong Zhang,Zhihua Li,Yining Ding 사단법인 한국계산역학회 2018 Computers and Concrete, An International Journal Vol.22 No.2

In order to evaluate the effect of hybrid fibers on the flexural performance of tunnel segment at room temperature, twelve reinforced self-consolidating concrete (SCC) symmetric inclination beams containing steel fiber, macro polypropylene fiber, micro polypropylene fiber, and their hybridizations were studied under combined loading of flexure and axial compression. The results indicate that the addition of mono steel fiber and hybrid fibers can enhance the ultimate bearing capacity and cracking behavior of tested beams. These improvements can be further enhanced along with increasing the content of steel fiber and macro PP fiber, but reduced with the increase of the reinforcement ratio of beams. The hybrid effect of steel fiber and macro PP fiber was the most obvious. However, the addition of micro PP fibers led to a degradation to the flexural performance of reinforced beams at room temperature. Meanwhile, the hybrid use of steel fiber and micro polypropylene fiber didn’t present an obvious improvement to SCC beams. Compared to micro polypropylene fiber, the macro polypropylene fiber plays a more prominent role on affecting the structural behavior of SCC beams. A calculation method for ultimate bearing capacity of flexural SCC symmetric inclination beams at room temperature by taking appropriate effect of hybrid fibers into consideration was proposed. The prediction results using the proposed model are compared with the experimental data in this study and other literature. The results indicate that the proposed model can estimate the ultimate bearing capacity of SCC symmetric inclination beams containing hybrid fibers subjected to combined action of flexure and axial compression at room temperature.

Superhydrophobic-Superoleophilic SiO2/Polystyrene Porous Micro/nanofibers for Efficient Oil-Water Separation

Yadan Ding,Dan Xu,Hong Shao,Tie Cong,Xia Hong,Huiying Zhao 한국섬유공학회 2019 Fibers and polymers Vol.20 No.10

SiO2/polystyrene porous micro/nanofibers with superhydrophobic and superoleophilic properties were preparedby facile electrospinning method. The spindle-beads-on-string structured fibers were found to be more hydrophobic thanthose without the beads. The doping of nano-SiO2 endowed the fibers with porous structure, and thus further increased thewater contact angle from 139 o to 153 o. Simultaneously, the oil contact angle of 0 o was obtained. The superhydrophobicsuperoleophilicmicro/nanofibers could selectively absorb oil from water within eight seconds. The oil sorption processfollowed pseudo-first order kinetic model. The absorption mechanism was proved to be physical encapsulation by Fouriertransform infrared technique. The maximum sorption capacity for highly viscous silicone oil was up to 122.7 g/g. It is higherthan many recently reported values. The porous micro/nanofibers exhibit significant value in oil-water separation.