检索结果-南通市图书馆

Fabrication of carbon-supported Al2O3 nanoparticles via spontaneous cross-linking to enhance selective hydrogenation of furfural

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2025年第1期100卷 612-620页

作者： Weiwei Yu Xinbao Zhang Hongyu chen Yanan Wang Shaoguo Li Fucun chen Zhenni Liu Xiujie Li Xiangxue Zhu State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Selective hydrogenation of furfural to furfuryl alcohol is a great challenge in the hydrogenation field due to thermodynamic preference for hydrogenation of C=C over C=***,a novel Al2O3/C-u hybrid catalyst,composed of N-modified dendritic carbon networks supporting Al2O3nanoparticles,was successfully prepared via carbonizing the freeze-dried gel from spontaneous cross-linking of alginate,Al3+and *** obtained carbon-supported Al2O3hybrid catalyst has a high ratio （31%） of Al species in pentahedral-coordinated *** introduction of urea enhances the surface N content,the ratio of pyrrolic N,and specific surface area of catalyst,leading to improved adsorption capacity of C=O and the accessibility of active *** the furfural hydrogenation reaction with isopropyl alcohol as hydrogen donor,Al2O3/C-u catalyst achieved a 90%conversion of furfural with 98.0% selectivity to furfuryl alcohol,outperforming that of commercial γ-***,Al2O3/C-u demonstrates excellent catalytic stability in the recycling tests attributed to the synergistic effect of abundant weak Lewis acid sites and the anchoring effect of the carbon network on *** work provides an innovative and facile strategy for fabrication of carbon-supported Al2O3hybrid catalysts with rich AlVspecies,serving as a high selective hydrogenation catalyst through MPV reaction route.

关键词： Selective hydrogenation Furfural Furfuryl alcohol Cross-linking MPV route

Feasibility analysis of a single-sensor-based approach for source identification of hazardous chemical releases

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2019年第7期27卷 1642-1650页

作者： Zengqiang chen lian Ye Bo Dai Fang Wang College of Information Engineering Beijing Institute of Petrochemical TechnologyBeijing 102617China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Office of Academic Affairs Beijing Institute of Petrochemical TechnologyBeijing 102617China

Source identification is critical for emergency responses to hazardous chemical releases,especially sudden releases of toxic *** timely arrangement of multiple sensors at the scene of a sudden accident is *** overcome this limitation,a two-step source identification method based on a single sensor was *** the first step,the measured concentration was transmitted to the computing ***,a preliminary estimation of the release source was calculated from recently detected ***,the preliminary result was used to predict the concentrations and to assess whether more measurements were *** data processing was conducted by the computing *** the second step,a new objective monitoring point was transmitted to the detector for the measurement of additional *** two steps were conducted repeatedly until the estimation adequately represented the release *** fixed and mobile single sensor results were analyzed,and a comparison to multi-sensor results was also *** results show that single-sensor source identification is attainable with a sufficient number of observations,and the number of valid concentration observations is required to be no less than the number of unknown *** best estimate the release source,the movement strategy of the single sensor was based on the possible release source and the hazard partition of the gas *** is highly recommended that the single-sensor source identification method be used in unexpected incidents due to its flexibility and timely response.

关键词： Safety analysis Emergency response Inverse problems Optimization Dispersion model

Preparation and characterization of a lipoid adsorption material and its atrazine removal performance

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2011年第8期23卷 1293-1298页

作者： Zhiqiang chen Qinxue Wen Jiaxiang lian Nanqi Ren State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology Harbin 150090 China. National Engineering Research Center of Urban Water Resources Harbin Institute of Technology Harbin 150090 China

A novel adsorbent named lipold adsorption material （LAM）, with a hydrophoblc nucleolus （trlolem） and a hydrophlllc membrane structure （polyamide）, was synthesized to remove hydrophobic organic chemicals （HOCs） from solution. Triolein, a type of lipoid, was entrapped by the polyamide membrane through an interfacial polymerization reaction. The method of preparation and the structure of the LAM were investigated and subsequent experiments were conducted to determine the characteristics of atrazine （a type of HOC） removal from wastewater using LAM as the adsorbent. The results showed that LAM had a regular structure compared with the prepolymer, where compact particles were linked with each other and openings were present in the structure of the LAM in which the fat drops formed from triolein were entrapped. In contrast to the atrazine adsorption behavior of powdered activated carbon （PAC）, LAM showed a persistent adsorption capacity for atrazine when initial concentrations of 0.57, 1.12, 8.31 and 19.01 mg/L were present, and the equilibrium time was 12 hr. Using an 8 mg/L initial concentration of atrazine as an indicator of HOCs in aqueous solution, experiments on the adsorption capacity of the LAM showed 69.3% removal within 6-12 hr contact time, which was close to the 75.5% removal of atrazine by PAC. Results indicated that LAM has two atrazine removal mechanisms, namely the bioaccumulation of atrazine by the nucleous material and physical adsorption to the LAM membrane. Bioaccumulation was the main removal mechanism.

关键词： lipoid adsorption material atrazine powdered activated carbon

Single Image Rain Removal Using Image Decomposition and a Dense Network

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2019年第6期6卷 1428-1437页

作者： Qiusheng lian Wenfeng Yan Xiaohua Zhang Shuzhen chen School of Information Science and Engineering Yanshan UniversityQinhuangdao 066004China School of Mathematics and Information Science and Technology Hebei Normal University of Science and TechnologyQinhuangdao 066004China

Removing rain from a single image is a challenging task due to the absence of temporal information. Considering that a rainy image can be decomposed into the low-frequency(LF) and high-frequency(HF) components, where the coarse scale information is retained in the LF component and the rain streaks and texture correspond to the HF component, we propose a single image rain removal algorithm using image decomposition and a dense network. We design two task-driven sub-networks to estimate the LF and non-rain HF components of a rainy image. The high-frequency estimation sub-network employs a densely connected network structure, while the low-frequency sub-network uses a simple convolutional neural network(CNN).We add total variation(TV) regularization and LF-channel fidelity terms to the loss function to optimize the two subnetworks jointly. The method then obtains de-rained output by combining the estimated LF and non-rain HF *** experiments on synthetic and real-world rainy images demonstrate that our method removes rain streaks while preserving non-rain details, and achieves superior de-raining performance both perceptually and quantitatively.

关键词： Convolutional neural network(CNN) dense network image decomposition rain removal total variation(TV)

Study of testability measurement method for equipment based on Bayesian network model

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2009年第5期20卷 1017-1023页

作者： lian Guangyao Huang Kaoli chen Jianhui Wei Zhonglin Ordnance Engineering Coll. Shijiazhuang 050003 P. R. China

To analyze and evaluate the testability design of equipment, a testability analysis method based on Bayesian network inference model is proposed in the paper. The model can adequately apply testability information and many uncertainty information of design and maintenance process, so it can analyze testability by and large from Bayesian inference. The detailed procedure to analyze and evaluate testability for equipments by Bayesian network is given in the paper. Its modeling process is simple, its formulation is visual, and the analysis results are more reliable than others. Examples prove that the analysis method based on Bayesian network inference can be applied to testability analysis and evaluation for complex equipments.

关键词： design for testability testability analysis and evaluation uncertainty information Bayesian network

Therapeutic effects of four strains of probiotics on experimental colitis in mice

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2009年第3期15卷 321-327页

作者： Lin-Lin chen xue-Hong Wang Yi Cui Guang-Hui lian Jie Zhang Chun-Hui Ouyang Fang-Gen Lu Department of Gastroenterology The Second Xiangya Hospital of Central South University Changsha 410011 Hunan Province China Department of Gastroenterology Zhongshan City People's Hospital Zhongshan 528400 Guangdong Province China

AIM:To investigate the therapeutic effects of four strains of probiotics(***,***,*** and ***) on dextran sulphate sodium(DSS)-induced experimental colitis in Balb/c ***:Eighty Balb/c mice were randomly divided into 8 ***-loss,fecal character,fecal occult blood and hematochezia were recorded *** activity index(DAI) scores were also evaluated *** of colon was measured and histological scores were evaluated on the 13th ***(MPO) activity was ***-1(IL-1) and IL-4 expression was detected by ELISA and ***:The four strains of probiotics relieved the inflammatory condition of DSS-induced experimental colitis in *** loss was slowed down in all probiotics-treated *** weight gain was observed by the end of probiotics *** DAI and histological scores of probiotics-treated mice were lower than those of mice in the control group(1.9 ± 0.2 vs 8.6 ± 0.4,P < 0.05 for ***).The length of colon of probiotics-treated mice was longer than that of mice in the control group(10.3 ± 0.34 vs 8.65 ± 0.77,P < 0.05 for ***).The four strains of probiotics decreased the MP activity and the IL-1 expression,but increased the IL-4 *** had a better effect on DSS-induced experimental colitis in mice than the other three ***:The four strains of probiotics have beneficial effects on experimental colitis in *** has a better effect on DSS-induced experimental colitis in mice than the other three *** of probiotics provides a new therapy for UC.

关键词： Probiotic E faecalis Experimental colitis Interleukin-1 Interleukin-4

Multiple Functional Biomass-Derived Activated Carbon Materials for Aqueous Supercapacitors, Lithium-Ion Capacitors and Lithium-Sulfur Batteries

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2017年第6期35卷 861-866页

作者： Kunfeng chen Dongfeng xue State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China

Biomass-derived activated carbon electrode materials have been synthesized by carbonization and KOH activa- tion processes from an agriculture waste - rice husk, composed of organic compound and silica. The surface area of activated carbon reached 1098.1 m2/g mainly including mesopores and macropores due to the template effect of sil- ica in rice husk. Owing to the existence of mesopores and macropores, the as-obtained activated carbon materials can be used in aqueous supercapacitors, lithium-ion （Li-ion） capacitors and lithium-sulfur （Li-S） batteries. In KOH electrolyte, fast rate performance （as high as 2 V/s） was obtained due to the existence of ideal electrical double layer capacitance. In organic electrolyte, high voltage （2.5 V） was achieved. Activated carbon electrode for Li-ion capac- itor also showed capacity of 17 mAh/g at 100 mA/g with the high voltage range of 2.5 V. The capacities of sul- fur-activated carbon in Li-S batteries were 1230 and 970 mAh/g at the current densities of 0.1 and 0.2 C. The pre- sent results showed that activated carbon materials with mesopores were good host to immobilize polysulfides.

关键词： activated carbon lithium ion capacitor rice husk biomass utilization organic electrolyte

Emerging roles of non-coding RNAs in epigenetic regulation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2016年第3期59卷 227-235页

作者： Juan chen Yuanchao xue Key Lab of RNA biology Institute of Biophysics Chinese academy of Sciences

Recent deep sequencing surveys of mammalian genomes have unexpectedly revealed pervasive and complex transcription and identified tens of thousands of RNA transcripts that do not code for proteins. These non-coding RNAs(nc RNAs) highlight the central role of RNA in gene regulation. nc RNAs are arbitrarily divided into two main groups: The first includes small RNAs, such as mi RNAs, pi RNAs, and endogenous si RNAs, that usually range from 20 to 30 nt, while the second group includes long non-coding RNAs(lnc RNAs), which are typically more than 200 nt in length. These nc RNAs were initially thought to merely regulate gene expression at the post-transcriptional level, but recent studies have indicated that nc RNAs, especially lnc RNAs, are extensively associated with diverse chromatin remodeling complexes and target them to specific genomic loci to alter DNA methylation or histone status. These findings suggest an emerging theme of nc RNAs in epigenetic regulation. In this review, we discuss the wide spectrum of nc RNAs in the regulation of DNA methylation and chromatin state, as well as the key questions that needs to be investigated and acknowledging the elegant design of these intriguing macromolecules.

关键词： non-coding RNAs lncRNAs DNA methylation chromatin remodeling

A 124 dB dynamic range sigma-delta modulator applied to non-invasive EEG acquisition using chopper-modulated input-scaling-down technique

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2022年第4期65卷 23-37页

作者： Kaiquan chen Mingyi chen Longlong chenG liang QI Guoxing WANG Yong lian Department of Micro/Nano Electronics Shanghai Jiao Tong University China Electronic Cloud Brain (Tianjin) Technology Co. Ltd.

With the advancement of brain science in recent years, the non-invasive brain-computer interfaces（BCIs） based on electroencephalogram（EEG） acquisition have been widely adopted in various brain-inspired applications. The acquisition of multi-channel microvolts EEG signals corrupted by the motion artifacts（MAs） of up to several volts poses enormous challenges to the design of analog front-end（AFE）, especially the analog-to-digital converter（ADC）, which is necessary to achieve low noise, wide dynamic range（DR）,high accuracy as well as low power. In this paper, a wide DR Σ△ modulator with chopper-modulated inputscaling-down（CM-ISD） technique has been proposed to deal with large input offset while extending dynamic range. Fabricated in 180 nm CMOS technology, the prototype occupies a core area of 0.32 mm;. With a 40 Hz input signal and 125 Hz Nyquist bandwidth, the measured signal-to-noise ratio（SNR） and signalto-noise and distortion ratio（SNDR） are 117 and 110 dB, respectively. Thanks to the proposed CM-ISD technique, the modulator is capable of withstanding a full-scale(4.5 V;) input whereas the measured DR has been extended from 99 to 124 dB. The power consumption is 2.75 mW under 5 V supply voltage,corresponding to 170.6 dB Schreier figure-of-merit（FoMS）. The multi-channel EEG acquisition has been demonstrated based on the proposed modulator, showing its potential in advanced non-invasive BCI systems.

关键词： Analog-to-digital converter (ADC) ΣΔ modulator brain computer interface electroencephalogram dynamic range motion artifacts

同方期刊数据库