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人工智能 3

ANSYS/LS-DYNA 1

Al-Cr203体系 1

Al₂O₃-M_xO_y 1

Al@AP/PVDF纳米复合材料 1

HBV相关疾病 1

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Nrf2/Keap1 系统 1

N∶P比值 1

PET酶 1

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Pd局域环境 1

Pt–Ba–Ce/γ-Al₂O₃ 催化剂，物理化学性质，NO_x存储和还原，NO_x 排放，H₂ 还原剂 1

RE-Si₃N₄ 1

Si/Al 比值 1

TC4钛合金 1

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洞察无有机模板合成沸石分子筛催化材料

王叶青,吴勤明,孟祥举,肖丰收

《工程（英文）》 2017年第3卷第4期页码 567-574 doi: 10.1016/J.ENG.2017.03.029

摘要：在此基础上，总结并揭示了在无有机模板的Na+ 体系中合成的沸石分子筛的微孔体积与Si/Al 比值的关系，即微孔体积越大，Si/Al 比值越小，这对于无有机模板条件下合成Si/Al 比值可调控的沸石分子筛和设计它们的合成路线具有重要意义

关键词：无有机模板合成沸石分子筛沸石晶种沸石导向剂溶液 Si/Al 比值

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The effect of hierarchical single-crystal ZSM-5 zeolites with different Si/Al ratios on its pore structure

Yuexin Hou, Xiaoyun Li, Minghui Sun, Chaofan Li, Syed ul Hasnain Bakhtiar, Kunhao Lei, Shen Yu, Zhao Wang, Zhiyi Hu, Lihua Chen, Bao-Lian Su

《化学科学与工程前沿（英文）》 2021年第15卷第2期页码 269-278 doi: 10.1007/s11705-020-1948-3

摘要： Hierarchical single-crystal ZSM-5 zeolites with different Si/Al ratios (Hier-ZSM-5- , where = 50, 100, 150 and 200) were synthesized using an ordered mesoporous carbon-silica composite as hard template. Hier-ZSM-5- exhibits improved mass transport properties, excellent mechanical and hydrothermal stability, and higher catalytic activity than commercial bulk zeolites in the benzyl alcohol self-etherification reaction. Results show that a decrease in the Si/Al ratio in hierarchical single-crystal ZSM-5 zeolites leads to a significant increase in the acidity and the density of micropores, which increases the final catalytic conversion. The effect of porous hierarchy on the diffusion of active sites and the final catalytic activity was also studied by comparing the catalytic conversion after selectively designed poisoned acid sites. These poisoned Hier-ZSM-5- shows much higher catalytic conversion than the poisoned commercial ZSM-5 zeolite, which indicates that the numerous intracrystalline mesopores significantly reduce the diffusion path of the reactant, leading to the faster diffusion inside the zeolite to contact with the acid sites in the micropores predominating in ZSM-5 zeolites. This study can be extended to develop a series of hierarchical single-crystal zeolites with expected catalytic performance.

关键词： hierarchical zeolites single crystalline interconnected pores improved diffusion performance benzyl alcohol self-etherification reaction

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Plasma enhanced chemical vapor deposition of excellent a-Si:H passivation layers for a-Si:H/c-Si heterojunction

Lei ZHAO,Wenbin ZHANG,Jingwei CHEN,Hongwei DIAO,Qi WANG,Wenjing WANG

《能源前沿（英文）》 2017年第11卷第1期页码 85-91 doi: 10.1007/s11708-016-0437-3

摘要： The intrinsic a-Si:H passivation layer inserted between the doped a-Si:H layer and the c-Si substrate is very crucial for improving the performance of the a-Si:H/c-Si heterojunction (SHJ) solar cell. The passivation performance of the a-Si:H layer is strongly dependent on its microstructure. Usually, the compact a-Si:H deposited near the transition from the amorphous phase to the nanocrystalline phase by plasma enhanced chemical vapor deposition (PECVD) can provide excellent passivation. However, at the low deposition pressure and low deposition power, such an a-Si:H layer can be only prepared in a narrow region. The deposition condition must be controlled very carefully. In this paper, intrinsic a-Si:H layers were prepared on n-type Cz c-Si substrates by 27.12 MHz PECVD at a high deposition pressure and high deposition power. The corresponding passivation performance on c-Si was investigated by minority carrier lifetime measurement. It was found that an excellent a-Si:H passivation layer could be obtained in a very wide deposition pressure and power region. Such wide process window would be very beneficial for improving the uniformity and the yield for the solar cell fabrication. The a-Si:H layer microstructure was further investigated by Raman and Fourier transform infrared (FTIR) spectroscopy characterization. The correlation between the microstructure and the passivation performance was revealed. According to the above findings, the a-Si:H passivation performance was optimized more elaborately. Finally, a large-area SHJ solar cell with an efficiency of 22.25% was fabricated on the commercial 156 mm pseudo-square n-type Cz c-Si substrate with the open-circuit voltage ( ) of up to 0.732 V.

关键词： PECVD high pressure and high power a-Si:H microstructure passivation heterojunction solar cell

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变形速率比值判据与猫山隧道工程验证

李世煇,宋军

《中国工程科学》 2002年第4卷第6期页码 85-91

摘要：

为了初步解决新奥法隧道工程支护初期缺乏有效的、定量的围岩稳定性判据以及塌方事故多见的技术难题，文章论述了变形速率比值判据假说的依据，得出阈值的方法及应用中常的五种典型情况；猫山公路隧道施工中正反两方面的演绎证明，两个断面应用变形速率比值判据预报险情，化险为夷，另一断面中止应用此判据后，发生大塌方；变形速率比值判据是一种典型信息法，是一种假说—演绎方法，是从定性到定量综合集成法的一种初步应用。

关键词：开放的复杂巨系统塌方事故变形速率比值判据典型信息法假说—演绎方法综合集成法

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Molecular aspects of MERS-CoV

null

《医学前沿（英文）》 2017年第11卷第3期页码 365-377 doi: 10.1007/s11684-017-0521-z

摘要：

Middle East respiratory syndrome coronavirus (MERS-CoV) is a betacoronavirus which can cause acute respiratory distress in humans and is associated with a relatively high mortality rate. Since it was first identified in a patient who died in a Jeddah hospital in 2012, the World Health Organization has been notified of 1735 laboratory-confirmed cases from 27 countries, including 628 deaths. Most cases have occurred in Saudi Arabia. MERS-CoV ancestors may be found in Old World bats of the Vespertilionidae family. After a proposed bat to camel switching event, transmission of MERS-CoV to humans is likely to have been the result of multiple zoonotic transfers from dromedary camels. Human-to-human transmission appears to require close contact with infected persons, with outbreaks mainly occurring in hospital environments. Outbreaks have been associated with inadequate infection prevention and control implementation, resulting in recommendations on basic and more advanced infection prevention and control measures by the World Health Organization, and issuing of government guidelines based on these recommendations in affected countries including Saudi Arabia. Evolutionary changes in the virus, particularly in the viral spike protein which mediates virus-host cell contact may potentially increase transmission of this virus. Efforts are on-going to identify specific evidence-based therapies or vaccines. The broad-spectrum antiviral nitazoxanide has been shown to have in vitro activity against MERS-CoV. Synthetic peptides and candidate vaccines based on regions of the spike protein have shown promise in rodent and non-human primate models. GLS-5300, a prophylactic DNA-plasmid vaccine encoding S protein, is the first MERS-CoV vaccine to be tested in humans, while monoclonal antibody, m336 has given promising results in animal models and has potential for use in outbreak situations.

关键词： MERS-CoV Saudi Arabia spike protein transmission evolution vaccine

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Analysis of the double-layer α-Si:H emitter with different doping concentrations for α-Si:H/c-Si heterojunction

Haibin HUANG,Gangyu TIAN,Tao WANG,Chao GAO,Jiren YUAN,Zhihao YUE,Lang ZHOU

《能源前沿（英文）》 2017年第11卷第1期页码 92-95 doi: 10.1007/s11708-016-0432-8

摘要： Double-layer emitters with different doping concentrations (DLE) have been designed and prepared for amorphous silicon/crystalline silicon (α-Si:H/c-Si) heterojunction solar cells. Compared with the traditional single layer emitter, both the experiment and the simulation (AFORS-HET, http://www.paper.edu.cn/html/releasepaper/2014/04/282/) prove that the double-layer emitter increases the short circuit current of the cells significantly. Based on the quantum efficiency (QE) results and the current-voltage-temperature analysis, the mechanism for the experimental results above has been investigated. The possible reasons for the increased current include the enhancement of the QE in the short wavelength range, the increase of the tunneling probability of the current transport and the decrease of the activation energy of the emitter layers.

关键词： double-layer emitter α-Si:H/c-Si heterojunction solar cell short circuit current quantum efficiency current-voltage-temperature

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High-level expression of recombinant IgG1 by CHO K1 platform

Ningning Xu, Jianfa Ou, Al-Karim (Al) Gilani, Lufang Zhou, Margaret Liu

《化学科学与工程前沿（英文）》 2015年第9卷第3期页码 376-380 doi: 10.1007/s11705-015-1531-5

摘要： The Chinese Hamster Ovary (CHO K1) cell was used to express a targeted anti-cancer monoclonal antibody by optimizing the platform of the construction of production cell line in this study. The adherent CHO K1 was first adapted to suspension culture in chemical defined medium. Then the glutamine synthetase (GS) vector was applied to construct a single plasmid to overexpress a monoclonal antibody IgG1. Post transfection, the production of cell pool was optimized by glutamine-free selection and amplification using various concentrations of methionine sulfoximine. The best cell pool of CHO K1/IgG1 was used to screen the top single clone using the limiting dilution cloning. Finally, a high IgG1 production of 780 mg/L was obtained from a batch culture. This study demonstrated that the construction of high producing cell line, from gene to clone, could be completed within six month and the gene amplification improved protein production greatly.

关键词： Chinese hamster ovary (CHO) monoclonal antibody IgG1 amplification cell line development

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滇池北部重点水域蓝绿藻季节性变动下水体N∶P比值变化研究

何锋,段昌群,杜劲松,韩亚平,郭艳英,潘珉,宋任彬

《中国工程科学》 2010年第12卷第6期页码 94-98

摘要：利用生态化学计量学分析，蓝藻和水体中N∶P比值没有固定性，表明蓝藻没有表现出强烈的化学计量特征，而蓝藻的季节性变动也没有导致本区域水体具化学计量特性。通过分析滇池水体N∶P比值与蓝藻生物量变化之间相关关系,相关系数为-0.308，表明富营养化水体中N∶P比率对蓝藻生物量直接影响不大。因此,只有通过降低水体中N和P的浓度，才能控制蓝藻的爆发。

关键词：滇池蓝绿藻 N∶P比值变化生态化学计量学

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Enhanced activation of persulfate using mesoporous silica spheres augmented Cu–Al bimetallic oxide particles

《化学科学与工程前沿（英文）》 2023年第17卷第10期页码 1581-1592 doi: 10.1007/s11705-023-2327-7

摘要： Herein, Cu–Al bimetallic oxide was synthesized and mixed with mesoporous silica spheres via a simple hydrothermal method. The prepared sample was then analyzed and employed to activate potassium peroxydisulfate for bisphenol A removal. Based on the results of X-ray diffraction, scanning electron microscopy, and energy dispersion spectroscopy, Cu–Al bimetallic oxide was determined as CuO-Al₂O₃, and mesoporous silica spheres were found around the these particles. At 30 min, a bisphenol A degradation level of 90% was achieved, and it remained at over 60% after five consecutive cycles, indicating the catalyst’s superior capacity and stability. In terms of removal performance, the radical pathway (including

SO 4 •‒

, OH •, and

O 2 •‒

) and singlet oxygen (

1 O 2

) played minor roles, while electron migration between bisphenol A, potassium peroxydisulfate, and the catalyst played a dominant role. The introduction of Al₂O₃ promoted the formation of surface oxygen vacancies, which improved ligand complex formation between potassium peroxydisulfate and the catalyst, thereby facilitating electron migration. Furthermore, mesoporous silica spheres augment not only enhanced bisphenol A adsorption but also alleviated Cu leaching. Overall, this work is expected to provide significant support for the rational development of catalysts with high catalytic activity for persulfate activation via surface electron migration.

关键词： Cu–Al bimetallic oxides mesoporous silica spheres peroxydisulfate bisphenol A

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Stability and dynamics of rotor system with 45° slant crack on shaft

Yanli LIN, Xiaohui SI, Fulei CHU

《机械工程前沿（英文）》 2011年第6卷第2期页码 203-213 doi: 10.1007/s11465-011-0131-4

摘要：

Crack on a shaft is one of the common damages in a rotor system. In this paper, transverse vibrations are calculated to compare the influences of transverse crack and slant crack on the rotor system. Results show that the vibration amplitude of the rotor system with a 45° slant crack on the shaft is larger than that with a transverse crack when the two types of crack have the same depth and the rotor system runs in the same condition. Stability and dynamic characteristics of the rotor system with a 45° slant crack on the shaft under torsional excitation are analyzed by considering opening and closing of the crack. It is shown that the instability of the transverse vibration of the rotor system increases with increasing difference between the bending stiffness in two main directions, and the vibration is stable when the two bending stiffness are identical. The spectrum analysis of the steady-state response reveals that the gravity and the eccentricity produce different frequency components, and when the two bending stiffness are identical, the multiple frequency components of the torsional excitation disappear. Further investigation shows that the vibration amplitudes in combined frequencies increase rapidly in transversal, torsional, and axial vibration with increasing slant crack depth. The results are helpful for the understanding the dynamic behavior of a rotor system with a slant crack on a shaft and can be used for the detection of the slant crack on a shaft.

关键词： rotor dynamics slant crack stability torsional excitation open and close

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Resistance to acid degradation, sorptivity, and setting time of geopolymer mortars

Osama A MOHAMED; Rania AL-KHATTAB; Waddah AL-HAWAT

《结构与土木工程前沿（英文）》 2022年第16卷第6期页码 781-791 doi: 10.1007/s11709-022-0862-9

摘要： Experimental evaluations were conducted to determine the water sorptivity, setting time, and resistance to a highly acidic environment, of mortar with alkali-activated ground granulated blast furnace slag (GBS) binder and also of combinations of fly ash and GBS binders. Binders were activated using mixtures of NaOH and Na₂SiO₃ solutions. The molarity of NaOH in the mixtures ranged from 10 mol·L⁻¹ to 16 mol·L⁻¹, and the Na₂SiO₃/NaOH ratio was varied from 1.5 to 2.5. Mortar samples were produced using three binder combinations: 1) GBS as the only binder; 2) blended binder with a slag-to-fly ash ratio of 3:1; and 3) mixed binder with 1:1 ratio of slag to fly ash. Mortar samples were mixed and cured at (22 ± 2) °C till the day of the test. The impact of activator solution alkalinity, activator ratio Na₂SiO₃/NaOH, GBS content on the rate of water absorption were evaluated. After 7, 28, and 90 d of immersion in a 10% sulfuric acid solution, the resistance of a geopolymer matrix to degradation was assessed by measuring the change in sample weight. The influence of solution alkalinity and relative fly ash content on setting times was investigated. Alkali-activated mortar with a slag-to-fly ash ratio of 3:1 had the least sorptivity compared to the two other binder combinations, at each curing age, and for mortars made with each of the NaOH alkaline activator concentrations. Mortar sorptivity decreased with age and sodium hydroxide concentrations, suggesting the production of geopolymerization products. No reduction in weight of sample occurred after immersion in the strong acid H₂SO₄ solution for three months, regardless of binder combination. This was due to the synthesis of hydration and geopolymerization products in the presence of curing water, which outweighed the degradation of the geopolymer matrix caused by sulfuric acid.

关键词： alkali-activated materials fly ash sorptivity durability of concrete sodium hydroxide sodium silicates reduction in CO₂ emissions sulfuric acid

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Mercury enrichment in

Chunhao Dai, Pufeng Qin, Zhangwei Wang, Jian Chen, Xianshan Zhang, Si Luo

《环境科学与工程前沿（英文）》 2017年第11卷第1期 doi: 10.1007/s11783-017-0892-z

摘要： Mercury enrichment in response to elevated atmospheric mercury concentrations in the organs of rape ( ) was investigated. Elevated soil mercury content had significant impact on mercury accumulation in rape stems, roots, seeds and seed coats. Leaf mercury in the leaves was mostly affected by atmospheric input while the stems were mostly affected by soil concentrations. Mercury in the aboveground plant tissue mainly derived from atmospheric absorption, and atmospheric mercury absorption in leaves was higher than that in the stems. Mercury enrichment in response to elevated atmospheric mercury concentrations in the organs of rape ( ) was investigated using an open top chamber fumigation experiment and a soil mercury enriched cultivation experiment. Results indicate that the mercury concentration in leaves and stems showed a significant variation under different concentrations of mercury in atmospheric and soil experiments while the concentration of mercury in roots, seeds and seed coats showed no significant variation under different atmospheric mercury concentrations. Using the function relation established by the experiment, results for atmospheric mercury sources in rape field biomass showed that atmospheric sources accounted for at least 81.81% of mercury in rape leaves and 32.29% of mercury in the stems. Therefore, mercury in the aboveground biomass predominantly derives from the absorption of atmospheric mercury.

关键词： Open top chamber Gaseous elemental mercury (GEM) Soil Mercury Brassica napus

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Effects of additive NaI on electrodeposition of Al coatings in AlCl

Tianyu Yao, Haiyan Yang, Kui Wang, Haiyan Jiang, Xiao-Bo Chen, Hezhou Liu, Qudong Wang, Wenjiang Ding

《化学科学与工程前沿（英文）》 2021年第15卷第1期页码 138-147 doi: 10.1007/s11705-020-1935-8

摘要： Effects of NaI as an additive on electrodeposition of Al coatings in AlCl -NaCl-KCl (80-10-10 wt-%) molten salts electrolyte at 150°C were investigated by means of cyclic voltammetry, chronopotentiometry, scanning electron microscopy and X-ray diffraction (XRD). Results reveal that addition of NaI in the electrolyte intensifies cathodic polarization, inhibits growth of Al deposits and increases number density of charged particles. The electrodeposition of Al coatings in the AlCl -NaCl-KCl molten salts electrolyte proceeds via three-dimensional instantaneous nucleation which however exhibits irrelevance with NaI. Galvanostatic deposition results indicate that NaI could facilitate the formation of uniform Al deposits. A compact coating consisting of Al deposits with an average particle size of 3 μm was obtained at a current density of 50 mA∙cm in AlCl -NaCl-KCl molten salts electrolyte with 10 wt-% NaI. XRD analysis confirmed that NaI could contribute to the formation of Al coating with a preferred crystallographic orientation along (220) plane.

关键词： NaI additive electrodeposition molten salts Al coating

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Laser ablation of block copolymers with hydrogen-bonded azobenzene derivatives

Jintang Huang, Youju Huang, Si Wu

《化学科学与工程前沿（英文）》 2018年第12卷第3期页码 450-456 doi: 10.1007/s11705-018-1735-6

摘要：

Supramolecular assemblies (PS-b-P4VP(AzoR)) are fabricated by hydrogen-bonding azobenzene derivatives (AzoR) to poly(4-vinyl pyridine) blocks of polystyrene-block-poly(4-vinyl pyridine) (PS-b-P4VP). PS-b-P4VP(AzoR) forms phase separated nanostructures with a period of ~75–105 nm. A second length scale structure with a period of 2 µm is fabricated on phase separated PS-b-P4VP(AzoR) by laser interference ablation. Both the concentration and the substituent of AzoR in PS-b-P4VP(AzoR) affect the laser ablation process. The laser ablation threshold of PS-b-P4VP(AzoR) decreases as the concentration of AzoR increases. In PS-b-P4VP(AzoR) with different substituents (R= CN, H, and CH₃), ablation thresholds follow the trend: PS-b-P4VP(AzoCN)<PS-b-P4VP(AzoCH₃)<PS-b-P4VP(AzoH). This result indicates that the electron donor group (CH₃) and the electron acceptor group (CN) can lower the ablation threshold of PS-b-P4VP(AzoR).

关键词： laser ablation block copolymers hydrogen-bond azobenzene derivatives supramolecular assembly

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Seismic retrofitting of severely damaged RC connections made with recycled concrete using CFRP sheets

Yasmin MURAD, Wassel AL BODOUR, Ahmed ASHTEYAT

《结构与土木工程前沿（英文）》 2020年第14卷第2期页码 554-568 doi: 10.1007/s11709-020-0613-8

摘要： An experimental and numerical program is carried out in this research to investigate the influence of CFRP sheets on the cyclic behavior of unconfined connections made with recycled concrete. Cement is partially replaced by silica fume, iron filling and pulverised fuel ash using two different percentages: 15% and 20%. Each specimen is partially loaded at the first stage and then specimens are repaired using CFRP sheets. The repaired specimens are then laterally loaded until failure. In addition, a finite element model is built in ABAQUS and verified using the experimental results. The experimental results have shown that the repaired specimens have regained almost double the capacity of the un-repaired specimens and hence the adopted repair configuration is recommended for retrofitting seismically vulnerable RC connections. Increasing cement replacement percentage by silica fume, fuel ash or iron filling from 15% to 20% has reduced joint carrying capacity and weakened the joint. It is recommended using 15% pulverised fuel ash or silica fume as cement partial replacement to enhance the strength and ultimate drift of beam-column joints under cyclic loading. Iron filling concrete is also recommended but the enhancement is relatively less than that found with pulverised fuel ash concrete and silica fume concrete.

关键词： retrofitting CFRP sheets recycled concrete pulverised fuel ash silica fume cyclic beam-column connections