Meshing performance investigations of involute worm and helical gear drive based on counterpart rack

Binbin Lu,Yonghong Chen,Shi-xuan Li,Bingkui Chen 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.8

Due to the involute worm and helical gear drive is different from the parallel shaft helical gear drive and the worm drive, the plane meshing theory and the space enveloping principle cannot be directly applied for this worm drive when the meshing analysis is performed, there has been no good analysis method to accurately calculate the meshing situation. To satisfy the increasing requirements of low-noise and long-lifetime in the service robots and the modern intelligent house systems, especially the intelligent shading system in the modern intelligent house system, a novel meshing performance analysis method is proposed for the involute worm and helical gear drive based on the counterpart rack. By calculating the contact line between the counterpart rack and helical gear and the contact line between the counterpart rack and involute worm, we can get the contact point of involute worm and helical gear finally. This novel meshing performance analysis makes it possible to use the plane meshing theory and the space enveloping principle to analyze involute worm and helical gear drive. The meshing relationship between the involute worm and the counterpart rack, as well as the counterpart rack and the helical gear are presented, and the computational model of contact ratio and contact ellipse are obtained through the counterpart rack. The mathematic model for the instantaneous contact point and contacts trace of the worm drive with different assembly errors is established, and the meshing performances are investigated through the numerical analysis, simulation analysis and performance testing. The results show that this worm drive is insensitively to the assembly errors, and it is beneficial for reducing the vibrationnoise and extending the service life. This theoretical research provides theoretical support for further optimizing the vibration and noise of involute worm and helical gear drive and improving the fatigue life.

Highly aligned indium zinc oxide nanowire-based artificial synapses with low-energy consumption

Lu Liu,Binbin Cui,Wenlong Xu,Yao Ni,Shuo Zhang,Wentao Xu 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.88 No.-

Emulating neural activities at individual synapse level has recently attracted tremendous attention. Here,we demonstrate design and fabrication of thefirst digitally aligned nanowire (NW)-based three-terminalsynaptic transistor. The highly-aligned and individually-position-controlled long continuous indium zincoxide (IZO) NW arrays were directly printed on a large area with low cost using a specialelectrohydrodynamic nanowire printing (e-NWP) process. The NWs printed by e-NWP with a diameterof 250 nm emulated the structure of nervefibers. The device emulates plasticity of biological synapsesand showed remarkable advantages in energy consumption compared with previous reports. Uniqueband-edge modulation along the NW axial direction underlies makes excellent electrical properties ofthe device. This approach paves the way to easy fabrication of printed-NW-based artificial neuralnetworks.

Identification of reference genes for normalization of gene expression in Liposcelis entomophila (Psocoptera: Liposcelididae)

Miao Shiyuan,Yang Binbin,Wang Suisui,Wang Zhengyan,Lu Yujie 한국응용곤충학회 2021 Journal of Asia-Pacific Entomology Vol.24 No.4

Liposcelis entomophila is a nuisance pest that seriously threatens the safety of stored grains owing in part of pesticide resistance. To facilitate better control of L. entomophila, future studies need to focus on gene function characterization. This requires the identification of suitable reference genes (RGs) for reverse-transcription quantitative PCR (RT-qPCR), which is crucial for the normalization of target gene expression. Here, we evalu ated the expression stability of 12 candidate RGs in L. entomophila across six experimental conditions (devel opmental stage, population, body part, phosphine fumigation, hypoxia induction, and temperature treatment). Under developmental conditions, ACTB, HSP70, and RPL23 were the most stable RGs. Among the different populations and body parts, RPL23, EF1a, and ACTB were the most stable RGs. Comparison of gene expression among adults under different environmental conditions revealed that at least seven RGs were fit for normalizing gene expression data. Among them, RPL23, EF1a, and ACTB showed the best fit as RGs in RT-qPCR analysis. After validation, our results demonstrated that EF1a and ACTB, as well as their combination, were the ideal RGs for L. entomophila across various experimental conditions. This study provides a comprehensive RG selection sug gestion for gene expression studies of L. entomophila and will facilitate future functional genomic research on the development and tolerance of environmental factors in psocids.

Hybrid ceramics-based cancer theranostics

Guan Qingwen,He Binbin,Huang Jie,Lu Helen H.,Wang Min 한국세라믹학회 2022 한국세라믹학회지 Vol.59 No.4

Cancer is a major threat to human lives. Early detection and precisely targeted therapy/therapies for cancer is the most eff ective way to reduce the diffi culties (e.g., side eff ects, low survival rate, etc.) in treating cancer. To enable eff ective can- cer detection and treatment, ceramic biomaterials have been intensively and extensively investigated owing to their good biocompatibility, high bioactivity, suitable biodegradability and other distinctive properties that are required for medical devices in oncology. Through hybridization with other materials and loading of imaging agents and therapeutic agents, nanobioceramics can form multifunctional nanodevices to simultaneously provide diagnostic and therapeutic functions for cancer patients, and these nanodevices are known as hybrid ceramics-based cancer theranostics. In this review, the recent developments of hybrid ceramics-based cancer theranostics, which include the key aspects such as their preparation, bio- logical evaluation and applications, are summarized and discussed. The challenges and future perspectives for the clinical translation of hybrid ceramics-based cancer theranostics are also discussed. It is believed that the potential of hybrid ceramic nanoparticles as cancer theranostics is high and that the future of these theranostics is bright despite the diffi culties along the way for their clinical translation.

Photocatalytic degradation of dyes using dioxygen activated by supported metallophthalocyanine under visible light irradiation

Yuyuan Yao,Zhenfu Huang,Binbin Zheng,Shun Zhu,Wangyang Lu,Wenxing Chen,Haixiang Chen 한국물리학회 2013 Current Applied Physics Vol.13 No.8

Zinc tetraaminophthalocyanine (Zn-TAPc) modified by cyanuric chloride was immobilized on silk fibers by covalent bond to obtain a supported photocatalyst (Zn-TDTAPc-SF). The photocatalytic degradation of acid orange II based on Zn-TDTAPc-SF/O2 system was investigated under visible light irradiation (λ ≥ 400 nm). The results indicated that Zn-TDTAPc-SF exhibited excellent photocatalytic performance in the presence of O2 under visible light irradiation. In 6 h, more than 93% of acid orange II (AO2) in Zn-TDTAPc-SF/O2 systemwas eliminated at initial pH 5 under visible light irradiation, and Zn-TDTAPc-SF still remained effective in repetitive fives cycles. Furthermore, NaCl played a positive role in the catalytic reaction, different from the negative one observed in homogeneous catalysis, and the reaction can proceed in a more wide pH range from acidic to alkaline. Based on the analysis of FT-IR and Gas Chromatography/Mass Spectrometry (GCeMS), AO2 was mainly converted into some small molecular biodegradable aliphatic carboxylic compounds such as maleic acid, fumaric acid, succinic acid, etc. The photodegradation mechanism for the evolution of AO2 was proposed by Electron Paramagnetic Resonance (EPR) spectra.