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三维电极反应器电吸附深度处理含砷废水（英文）

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Journal of Central South University 2024年第2期 443-459页

作者：罗永健王云燕何紫彤许欢孙竹梅 School of Metallurgy and Environment Central South University Chinese national engineering research center for Control & Treatment of Heavy Metal Pollution School of Environment and Safety engineering North University of China

水环境中砷的深度处理对减少环境污染和确保人类健康至关重要。自制了三维电极反应器,以活性炭颗粒为粒子电极材料,采用电吸附和物理/化学吸附联合模式实现As(Ⅴ)的深度处理。经优化后,As(Ⅴ)浓度可从0.5 mg/L降至0.032 mg/L,且均以H2As... 详细信息

水环境中砷的深度处理对减少环境污染和确保人类健康至关重要。自制了三维电极反应器,以活性炭颗粒为粒子电极材料,采用电吸附和物理/化学吸附联合模式实现As(Ⅴ)的深度处理。经优化后,As(Ⅴ)浓度可从0.5 mg/L降至0.032 mg/L,且均以H2AsO4-形式存在,无As(Ⅲ),表明不存在氧化还原反应。动力学研究发现,电吸附过程可分为三步:从溶液到电极材料表面的液膜扩散过程、从电极材料表面到内部孔隙的内扩散过程和电吸附接近平衡状态。为验证该工艺的循环性能,开展了电吸附-电脱附工艺研究,发现经过8次循环后,出水浓度仍仅为0.098 mg/L(低于0.1 mg/L的标准限值),实现了含砷废水的高效深度处理,但去除效率需提升、吸附后材料的处理仍需改进。

关键词：电吸附砷活性炭颗粒三维电极反应器砷的去除

Improvement of laser damage thresholds of fused silica by ultrasonic-assisted hydrofluoric acid etching

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Chinese Physics B 2017年第11期26卷 510-514页

作者：李源严鸿维杨科姚彩珍王志强闫春燕邹鑫书袁晓东杨李茗巨新 University of Science and Technology Beijing Department of Physics China Academy of engineering Physics Laser Fusion Research Center Fine Optical engineering research center

Polished fused silica samples were etched for different durations by using hydrofluoric（HF） acid solution with HF concentrations in an ultrasonic field. Surface and subsurface polishing residues and molecular structure parameters before and after the etching process were characterized by using a fluorescence microscope and infrared（IR） spectrometer, respectively. The laser induced damage thresholds（LIDTs） of the samples were measured by using pulsed nanosecond laser with wavelength of 355 nm. The results showed that surface and subsurface polishing residues can be effectively reduced by the acid etching process, and the LIDTs of fused silica are significantly improved. The etching effects increased with the increase of the HF concentration from 5 wt.% to 40 wt.%. The amount of polishing residues decreased with the increase of the etching duration and then kept stable. Simultaneously, with the increase of the etching time, the mechanical strength and molecular structure were improved.

关键词： HF etching fused silica laser induced damage threshold infrared spectra

Optoelectronic sensing of biophysical and biochemical signals based on photon recycling of a micro-LED

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Nano research 2021年第9期14卷 3208-3213页

作者： He Ding Guoqing Lv Zhao Shi Dali Cheng Yang Xie Yunxiang Huang Lan Yin Jian Yang Yongtian Wang Xing Sheng Beijing engineering research center of Mixed Reality and Advanced Display School of Optics and PhotonicsBeijing Institute of TechnologyBeijing 100081China Department of Electronic engineering Beijing National Research Center for Information Science and TechnologyCenter for Flexible Electronics TechnologyTsinghua UniversityBeijing 100084China School of Materials Science and engineering Tsinghua UniversityBeijing 100084China

Conventional bioelectrical sensors and systems integrate multiple power harvesting,signal amplification and data transmission components for wireless biological signal *** paper reports the real-time biophysical and biochemical activities can be optically captured using a microscale light-emitting diode(micro-LED),eliminating the need for complicated sensing *** a thin-film diode based device simultaneously absorbs and emits photons,enabling wireless power harvesting and signal ***,owing to its strong photon-recycling effects,the micro-LED^photoluminescence(PL)emission exhibits a superlinear dependence on the external *** advantage of these unique mechanisms,instantaneous biophysical signals including galvanic skin response,pressure and temperature,and biochemical signals like ascorbic acid concentration,can be optically monitored,and it demonstrates that such an optoelectronic sensing technique outperforms a traditional tethered,electrically based sensing circuit,in terms of its footprint,accuracy and *** presented optoelectronic sensing approach could establish promising routes to advanced biological sensors.

关键词： photon recycling photoluminescence microscale light-emitting diodes(micro-LEDs) optoelectronics biosensors

Optimization and evaluation of a bottom substrate denitrification tank for nitrate removal from a recirculating aquaculture system

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Journal of Environmental Sciences 2013年第8期25卷 1557-1564页

作者： Wiboonluk Pungrasmi Cholticha Playchoom Sorawit Powtongsook Department of Environmental engineering Faculty of Engineering Chulalongkorn University center of Excellence for Marine Biotechnology Department of Marine Science Faculty of Science Chulalongkorn University national center for Genetic engineering and Biotechnology National Science and Technology Development Agency

A bottom substrate denitrification tank for a recirculating aquaculture system was developed. The laboratory scale denitrification tank was an 8 L tank （0.04 m2 tank surface area）, packed to a depth of 5 cm with a bottom substrate for natural denitrifying bacteria. An aquarium pump was used for gentle water mixing in the tank; the dissolved oxygen in the water was maintained in aerobic conditions （e.g. 〉 2 mg/L） while anoxic conditions predominated only at the bottom substrate layer. The results showed that, among the four substrates tested （soil, sand, pumice stone and vermiculite）, pumice was the most preferable material. Comparing carbon supplementation using methanol and molasses, methanol was chosen as the carbon source because it provided a higher denitrification rate than molasses. When methanol was applied at the optimal COD：N ratio of 5：1, a nitrate removal rate of 4591 ± 133 mg-N/m2 tank bottom area/day was achieved. Finally, nitrate removal using an 80 L denitrification tank was evaluated with a 610 L recirculating tilapia culture system. Nitrate treatment was performed by batch transferring high nitrate water from the nitrification tank into the denitrification tank and mixing with methanol at a COD：N ratio of 5：1. The results from five batches of nitrate treatment revealed that nitrate was successfully removed from water without the accumulation of nitrite and ammonia. The average nitrate removal efficiency was 85.17% and the average denitrification rate of the denitrification tank was 6311 ± 945 mg-N/m2 tank bottom area/day or 126 ± 18 mg-N/L of pumice packing volume/day.

关键词： denitrification nitrate removal methanol pumice stone recirculating aquaculture system

Strategies on biosynthesis and production of bioactive compounds in medicinal plants

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Chinese Herbal Medicines 2024年第1期16卷 13-26页

作者： Miaoxian Guo Haizhou Lv Hongyu Chen Shuting Dong Jianhong Zhang Wanjing Liu Liu He Yimian Ma Hua Yu Shilin Chen Hongmei Luo Key Lab of Chinese Medicine Resources Conservation State Administration of Traditional Chinese Medicine of ChinaInstitute of Medicinal Plant DevelopmentChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100193China engineering research center of Chinese Medicine Resource Ministry of EducationBeijing 100193China Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration College of Life and Environmental SciencesHangzhou Normal UniversityHangzhou 311121China Chengdu University of Traditional Chinese Medicine Chengdu 611137China

Medicinal plants are a valuable source of essential medicines and herbal products for healthcare and disease *** with chemical synthesis and extraction,the biosynthesis of natural products is a very promising alternative for the successful conservation of medicinal plants,and its rapid development will greatly facilitate the conservation and sustainable utilization of medicinal ***,we summarize the advances in strategies and methods concerning the biosynthesis and production of natural products of medicinal *** strategies and methods mainly include genetic engineering,plant cell culture engineering,metabolic engineering,and synthetic biology based on multiple“OMICS”technologies,with paradigms for the biosynthesis of terpenoids and *** also highlight the biosynthetic approaches and discuss progress in the production of some valuable natural products,exemplifying compounds such as vindoline(alkaloid),artemisinin and paclitaxel(terpenoids),to illustrate the power of biotechnology in medicinal plants.

关键词： biosynthetic strategies biotechnology natural products medicinal plants synthetic biology

GSH-induced chemotaxis nanomotors for cancer treatment by ferroptosis strategy

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Science China Chemistry 2022年第5期65卷 989-1002页

作者： Zhiyong Liu Ting Li Nan Li Yujing Wang Lin Chen Xueting Tang Mimi Wan Chun Mao national and Local Joint engineering research center of Biomedical Functional Materials School of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China

Overexpression of glutathione(GSH) in tumor cells greatly inhibits the therapy effect of traditional ferroptosis inducers;thus,control of the GSH level is an important way to improve the efficacy of ***,a kind of nanomotor based on metal organic framework material NH_(2)-MIL-101 is constructed,in which polyethylene glycol(PEG) and glutathione hydrolase γ-glutamyltransferase(GGT) are asymmetrically modified to obtain mPEG@MIL-101@GGT nanomotors(PMG NMs).The nanomotor proposed in this article can be induced by overexpressing GSH in tumors to form chemotactic effects through the specific affinity between enzymes and *** indicate that the tail structure provided by PEG and the affinity between GGT and GSH can enable the stable chemotaxis behavior of nanomotors in a complex environment,thus enriching and penetrating deeply at the tumor *** addition,after loading the ferroptosis inducer Erastin,the system shows a highly effective induction effect of tumor *** in the system can effectively inhibit the synthesis of GSH,and PMG NMS can react with GSH through Fe^(3+)and GGT to promote GSH *** produced Fe^(2+)can generate excessive reactive oxygen species through Fenton reaction,which further promotes the death of tumor ***,the chemotaxis behavior of the nanomotors based on the endogenous biochemical reaction of GGT-catalyzed GSH hydrolysis can endow nanomotors with the enhanced delivery and penetration ability in tumors,thus collaboratively enhancing the ferroptosis *** strategy designed according to the physiological characteristics of tumors has good biosafety and treatment effect,providing new perspectives for micro/nanomotor and tumor treatment.

关键词： chemotaxis nanomotors ferroptosis glutathione depletion cancer therapy

Relationship between crystal growth mode, preferred orientation and magnetostriction of (Tb_(0.3)Dy_(0.7))Fe_(1.95) alloys

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Journal of Rare Earths 2008年第3期26卷 388-391页

作者：张世荣李扩社于敦波李勇胜杨红川李红卫涂赣峰 School of Materials and Metallurgy Northeastern University national engineering research center for Rare Earth Materials General Research Institute for Non-Ferrous Metals Grirem Advanced Materials Co. Ltd. Beijing 100088 China national engineering research center for Rare Earth Materials General Research Institute for Non-Ferrous Metals Grirem Advanced Materials Co. Ltd.

The relationship between crystal growth mode, preferred orientation and magnetostrictive properties of （Tb0.3Dy0.7）Fe1.95 alloys was investigated at different directional solidification rates. The results showed that preferred orientation had a strong influence on the characteristics of （Tb0.3Dy0.7）Fe1.95 alloys. At lower solidification rates, the sample with 〈110〉 preferred orientation showed larger low-field magnetostriction and apparent compressive stress effect. The excessive solidification rate resulted in failure of preferred orientation and a poor magnetostrictive performance. With an increase in solidification rates, the crystal growth modes changed gradually from cellular and primary dendrite morphology to developed dendritic morphology. In addition, domain configurations were observed using magnetic force microscopy, and the change of magnetostrictive properties was interpreted in terms of revealing the domain configurations.

关键词： preferred orientation TbDyFe magnetostriction magnetic domain structure rare earths

Estimating Wheat Grain Protein Content Using Multi-Temporal Remote Sensing Data Based on Partial Least Squares Regression

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Journal of Integrative Agriculture 2012年第9期11卷 1445-1452页

作者： LI Cun-jun WANG Ji-hua WANG Qian WANG Da-cheng SONG Xiao-yu WANG Yan HUANGWen-jiang Beijing research center for Information Technology in Agriculture Beijing 100097 P.R.China national engineering research center for Information Technology in Agriculture Beijing 100097 P.R.China

Estimating wheat grain protein content by remote sensing is important for assessing wheat quality at maturity and making grains harvest and purchase policies. However, spatial variability of soil condition, temperature, and precipitation will affect grain protein contents and these factors usually cannot be monitored accurately by remote sensing data from single image. In this research, the relationships between wheat protein content at maturity and wheat agronomic parameters at different growing stages were analyzed and multi-temporal images of Landsat TM were used to estimate grain protein content by partial least squares regression. Experiment data were acquired in the suburb of Beijing during a 2-yr experiment in the period from 2003 to 2004. Determination coefficient, average deviation of self-modeling, and deviation of cross- validation were employed to assess the estimation accuracy of wheat grain protein content. Their values were 0.88, 1.30%, 3.81% and 0.72, 5.22%, 12.36% for 2003 and 2004, respectively. The research laid an agronomic foundation for GPC （grain protein content） estimation by multi-temporal remote sensing. The results showed that it is feasible to estimate GPC of wheat from multi-temporal remote sensing data in large area.

关键词： grain protein content agronomic parameters multi-temporal Landsat partial least squares regression

High Quality Audio Object Coding Framework Based on Non-Negative Matrix Factorization

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China Communications 2017年第9期14卷 32-41页

作者： Tingzhao Wu Ruimin Hu Xiaochen Wang Shanfa Ke Jinshan Wang national engineering research center for Multimedia Software School of Computer ScienceWuhan University Hubei Key Laboratory of Multimedia and Network Communication engineering Wuhan University Collaborative Innovation center of Geospatial Technology

Object-based audio coding is the main technique of audio scene coding. It can effectively reconstruct each object trajectory, besides provide sufficient flexibility for personalized audio scene reconstruction. So more and more attentions have been paid to the object-based audio coding. However, existing object-based techniques have poor sound quality because of low parameter frequency domain resolution. In order to achieve high quality audio object coding, we propose a new coding framework with introducing the non-negative matrix factorization(NMF) method. We extract object parameters with high resolution to improve sound quality, and apply NMF method to parameter coding to reduce the high bitrate caused by high resolution. And the experimental results have shown that the proposed framework can improve the coding quality by 25%, so it can provide a better solution to encode audio scene in a more flexible and higher quality way.

关键词： object-based audio coding non-negative matrix factorization audio scenecoding