PbICl precursor solutions for all solid-state PbS quantum-dot sensitized TiO2 nanorod array solar cells using successive ionic layer adsorption and reaction method

Kai Lv,Chengwu Shi,Zhengguo Zhang,Chengfeng Ma,Qi Wang 한국물리학회 2018 Current Applied Physics Vol.18 No.6

In this work, PbICl precursor solution in N,N-dimethylformamide was successfully applied to deposit PbS quantum-dots on TiO2 nanorod arrays by successive ionic layer adsorption and reaction method (SILAR). The influence of PbI2, PbBr2, PbICl precursor solution on the morphology, crystal size and optical absorption of PbS quantum-dots was investigated and the photovoltaic performance of the corresponding solid-state PbS quantumdot sensitized TiO2 nanorod array solar cells with spiro-OMeTAD was evaluated. The average crystal sizes of PbS quantum-dots were 9.0 nm of PbI2, 8.6 nm of PbBr2 and 8.4 nm of PbICl and the photoelectric conversion efficiency of the corresponding solar cells achieved 2.63%, 3.00%, 3.45%. The result revealed that PbICl precursor solution was superior to PbBr2 and PbI2.

Repetitive Control with Specific Harmonic Gain Compensation for Cascaded Inverters under Rectifier Loads

Lv, Zheng-Kai,Sun, Li,Duan, Jian-Dong,Tian, Bing,Qin, HuiLing The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.6

The further improvement of submarine propulsion is associated with the modularity of accumulator-fed inverters, such as cascaded inverters (CIs). CI technology guarantees smooth output voltages with reduced switch frequencies under linear loads. However, the output voltages of CIs are distorted under rectifier loads. This distortion requires harmonic suppression technology. One such technology is the repetitive controller (RC), which is commonly applied but suffers from poor performance in propulsion systems. In this study, the FFT spectrum of a CI under rectifier load is analyzed, and the harmonic contents are uneven in magnitude. For the purpose of harmonic suppression, the control gains at each harmonic frequency should be seriously considered. A RC with a specific harmonic gain compensation (SHGC) for CIs is proposed. This method provides additional control gains at low-order harmonic frequencies, which are difficult to achieve with conventional RCs. This SHGC consists of a band-pass filter (BPF) and proportional element and is easy to implement. These features make the proposed method suitable for submarine propulsion. Experimental results verify the feasibility of the improved RC.

Repetitive Control with Specific Harmonic Gain Compensation for Cascaded Inverters under Rectifier Loads

Zheng-Kai Lv,Li Sun,Jian-Dong Duan,Bing Tian,HuiLing Qin 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.6

The further improvement of submarine propulsion is associated with the modularity of accumulator-fed inverters, such as cascaded inverters (CIs). CI technology guarantees smooth output voltages with reduced switch frequencies under linear loads. However, the output voltages of CIs are distorted under rectifier loads. This distortion requires harmonic suppression technology. One such technology is the repetitive controller (RC), which is commonly applied but suffers from poor performance in propulsion systems. In this study, the FFT spectrum of a CI under rectifier load is analyzed, and the harmonic contents are uneven in magnitude. For the purpose of harmonic suppression, the control gains at each harmonic frequency should be seriously considered. A RC with a specific harmonic gain compensation (SHGC) for CIs is proposed. This method provides additional control gains at low-order harmonic frequencies, which are difficult to achieve with conventional RCs. This SHGC consists of a band-pass filter (BPF) and proportional element and is easy to implement. These features make the proposed method suitable for submarine propulsion. Experimental results verify the feasibility of the improved RC.

Facile Synthesis of Co₃O₄/Mildly Oxidized Multiwalled Carbon Nanotubes/Reduced Mildly Oxidized Graphene Oxide Ternary Composite as the Material for Supercapacitors

Lv, Mei-Yu,Liu, Kai-Yu,Li, Yan,Wei, Lai,Zhong, Jian-Jian,Su, Geng Korean Chemical Society 2014 Bulletin of the Korean Chemical Society Vol.35 No.5

A three-dimensional (3D) $Co_3O_4$/mildly oxidized multiwalled carbon nanotubes (moCNTs)/reduced mildly oxidized graphene oxide (rmGO) ternary composite was prepared via a simple and green hydrolysishydrothermal approach by mixing $Co(Ac)_2{\cdot}4H_2O$ with moCNTs and mGO suspension in mixed ethanol/$H_2O$. As characterized by scanning electron microscopy and transmission electron microscopy, $Co_3O_4$ nanoparticles with size of 20-100 nm and moCNTs are effectively anchored in mGO. Cyclic voltammetry and galvanostatic charge-discharge measurements were adopted to investigate the electrochemical properties of $Co_3O_4$/moCNTs/rmGO ternary composite in 6 M KOH solution. In a potential window of 0-0.6 V vs. Hg/HgO, the composite delivers an initial specific capacitance of 492 $Fg^{-1}$ at 0.5 $Ag^{-1}$ and the capacitance remains 592 $Fg^{-1}$ after 2000 cycles, while the pure $Co_3O_4$ shows obviously capacitance fading, indicating that rmGO and moCNTs greatly enhance the electrochemical performance of $Co_3O_4$.

Covered Stenting Is an Effective Option for Traumatic Carotid Pseudoaneurysm with Promising Long-Term Outcome

Kai Wang,Xiao-xin Peng,Ao-fei Liu,Ying-ying Zhang,Jin Lv,Li Xiang,Yun-e Liu,Wei-jian Jiang 대한신경외과학회 2020 Journal of Korean neurosurgical society Vol.63 No.5

Objective : Covered stenting is an optional strategy for traumatic carotid pseudoaneurysm, especially in malignant conditions of potential rupture, but the long-term outcomes are not clear. Our aim was to determine if covered stenting is an effective option for traumatic carotid pseudoaneurysm with promising long-term outcomes. Methods : Self-expanding Viabahn and balloon-expandable Willis covered stents were separately implanted for extra- and intracranial traumatic carotid pseudoaneurysm. The covered stent was placed across the distal and proximal pseudoaneurysm leakage under roadmap guidance. Procedural success was defined as technical success (complete exclusion of the pseudoaneurysm and patency of the parent artery) without a primary end point (any stroke or death within 30 days after the procedure). Longterm outcomes were evaluated as ischemic stroke in the territory of the qualifying artery by clinical follow-up through outpatient or telephone consultation and as the exclusion of the pseudoaneurysm and patency of the parent artery by imaging follow-up through angiography. Results : Five patients with traumatic carotid pseudoaneurysm who underwent covered stenting were enrolled. The procedural success rate was 100%. No ischemic stroke in the territory of the qualifying artery was recorded in any of the five patients during a mean clinical follow-up of 44±16 months. Complete exclusion of the pseudoaneurysm and patency of the parent artery were maintained in all five patients during a mean imaging follow-up of 39±16 months. Conclusion : Satisfactory procedural and long-term outcomes were obtained, suggesting that covered stenting is an effective option for traumatic carotid pseudoaneurysm.

Covered Stenting Is an Effective Option for Traumatic Carotid Pseudoaneurysm with Promising Long-Term Outcome

Wang, Kai,Peng, Xiao-xin,Liu, Ao-fei,Zhang, Ying-ying,Lv, Jin,Xiang, Li,Liu, Yun-e,Jiang, Wei-jian The Korean Neurosurgical Society 2020 Journal of Korean neurosurgical society Vol.63 No.5

Objective : Covered stenting is an optional strategy for traumatic carotid pseudoaneurysm, especially in malignant conditions of potential rupture, but the long-term outcomes are not clear. Our aim was to determine if covered stenting is an effective option for traumatic carotid pseudoaneurysm with promising long-term outcomes. Methods : Self-expanding Viabahn and balloon-expandable Willis covered stents were separately implanted for extra- and intracranial traumatic carotid pseudoaneurysm. The covered stent was placed across the distal and proximal pseudoaneurysm leakage under roadmap guidance. Procedural success was defined as technical success (complete exclusion of the pseudoaneurysm and patency of the parent artery) without a primary end point (any stroke or death within 30 days after the procedure). Long-term outcomes were evaluated as ischemic stroke in the territory of the qualifying artery by clinical follow-up through outpatient or telephone consultation and as the exclusion of the pseudoaneurysm and patency of the parent artery by imaging follow-up through angiography. Results : Five patients with traumatic carotid pseudoaneurysm who underwent covered stenting were enrolled. The procedural success rate was 100%. No ischemic stroke in the territory of the qualifying artery was recorded in any of the five patients during a mean clinical follow-up of 44±16 months. Complete exclusion of the pseudoaneurysm and patency of the parent artery were maintained in all five patients during a mean imaging follow-up of 39±16 months. Conclusion : Satisfactory procedural and long-term outcomes were obtained, suggesting that covered stenting is an effective option for traumatic carotid pseudoaneurysm.

Facile Synthesis of Zn1-xCuxO Nanorods with a Very Broad Visible Band

Jianguo Lv,Changlong Liu,Wanbing Gong,Zhenfa Zi,Xiaoshuang Chen,Kai Huang,Feng Liu,Tao Wang,Gang He,Xueping Song,Zhaoqi Sun 대한금속·재료학회 2012 ELECTRONIC MATERIALS LETTERS Vol.8 No.5

Zn1-xCuxO nanorods with different Cu concentrations are prepared by a hydrothermal method. Bent and aggregated nanorods are obtained, which is attributed to centripetal surface tension of the evaporation and coagulation processes of the water film on the ZnO nanorods. The broad visible band consists of one violet, three blue,and one green emission. The violet emission is due to the transition of electrons from zinc interstitial (Zni)levels to the valance band. The three blue emissions may be attributed to the transition from extended Zni levels, which are slightly below the simple Zni level, to the valance band. The change of the green emission may be the result of competition between oxygen vacancies (VO) and zinc vacancies (VZn).

Facile Synthesis of Co3O4/Mildly Oxidized Multiwalled Carbon Nanotubes/Reduced Mildly Oxidized Graphene Oxide Ternary Composite as the Material for Supercapacitors

Mei-yu Lv,Kai-yu Liu,Yan Li,Lai Wei,Jian-jian Zhong,Geng Su 대한화학회 2014 Bulletin of the Korean Chemical Society Vol.35 No.5

A three-dimensional (3D) Co3O4/mildly oxidized multiwalled carbon nanotubes (moCNTs)/reduced mildly oxidized graphene oxide (rmGO) ternary composite was prepared via a simple and green hydrolysishydrothermal approach by mixing Co(Ac)2·4H2O with moCNTs and mGO suspension in mixed ethanol/H2O. As characterized by scanning electron microscopy and transmission electron microscopy, Co3O4 nanoparticles with size of 20-100 nm and moCNTs are effectively anchored in mGO. Cyclic voltammetry and galvanostatic charge-discharge measurements were adopted to investigate the electrochemical properties of Co3O4/moCNTs/ rmGO ternary composite in 6 M KOH solution. In a potential window of 0-0.6 V vs. Hg/HgO, the composite delivers an initial specific capacitance of 492 F g−1 at 0.5 A g−1 and the capacitance remains 592 F g−1 after 2000 cycles, while the pure Co3O4 shows obviously capacitance fading, indicating that rmGO and moCNTs greatly enhance the electrochemical performance of Co3O4.

Role of Preoperative Albumin Quotient in Surgical Planning for Posttraumatic Syringomyelia: A Comparative Cohort Study

Pingchuan Xia,Houyuan Lv,Chenghua Yuan,Wanru Duan,Jiachen Wang,Jian Guan,Yueqi Du,Can Zhang,Zhenlei Liu,Kai Wang,Zuowei Wang,Xingwen Wang,Hao Wu,Zan Chen,Fengzeng Jian 대한척추신경외과학회 2024 Neurospine Vol.21 No.1

Objective: Surgical procedures for patients with posttraumatic syringomyelia (PTS) remain controversial. Until now, there have been no effective quantitative evaluation methods to assist in selecting appropriate surgical plans before surgery. Methods: We consecutively enrolled PTS patients (arachnoid lysis group, n = 42; shunting group, n = 14) from 2003 to 2023. Additionally, 19 intrathecal anesthesia patients were included in the control group. All patients with PTS underwent physical and neurological examinations and spinal magnetic resonance imaging preoperatively, 3–12 months postoperatively and during the last follow-up. Preoperative lumbar puncture was performed and blood-spinal cord barrier disruption was detected by quotient of albumin (Qalb, cerebrospinal fluid/serum). Results: The ages (p = 0.324) and sex (p = 0.065) of the PTS and control groups did not differ significantly. There were also no significant differences in age (p = 0.216), routine blood data and prognosis (p = 0.399) between the arachnoid lysis and shunting groups. But the QAlb level of PTS patients was significantly higher than that of the control group (p < 0.001), and the shunting group had a significantly higher QAlb (p < 0.001) than the arachnoid lysis group. A high preoperative QAlb (odds ratio, 1.091; 95% confidence interval, 1.004–1.187; p = 0.041) was identified as the predictive factor for the shunting procedure, with the receiver operating characteristic curve showing 100% specificity and 80.95% sensitivity for patients with a QAlb > 12.67. Conclusion: Preoperative QAlb is a significant predictive factor for the types of surgery. For PTS patients with a QAlb > 12.67, shunting represents the final recourse, necessitating the exploration and development of novel treatments for these patients.

Overexpression of Long Non-Coding RNA HOTAIR Promotes Tumor Growth and Metastasis in Human Osteosarcoma

Bo Wang,Yun Su,Qun Yang,Decheng Lv,Wei-Guo Zhang,Kai Tang,Hong Wang,Rui Zhang,Yang Liu 한국분자세포생물학회 2015 Molecules and cells Vol.38 No.5

Human osteosarcoma usually presented a high tendency to metastatic spread and caused poor outcomes, however, the underlying mechanism was still largely unknown. In the present study, using a series of in vitro experiments and an animal model, we investigated the roles of HOX antisense intergenic RNA (HOTAIR) during the proliferation and invasion of osteosarcoma. According with our results, HOTAIR was commonly overexpressed in osteosarcoma, which significantly correlated with advanced tumor stage, highly histological grade and poor prognosis. In vitro and in vivo experiments demonstrated that knockdown of HOTAIR could notably suppress cellular proliferation, inhibit invasion and decrease the secretion of MMP2 and MMP9 in osteosarcoma. Collectively, our results suggested that HOTAIR might be a potent therapeutic target for osteosarcoma.