资源类型

期刊论文 249

会议视频 3

年份

2024 1

2023 23

2022 25

2021 22

2020 20

2019 12

2018 19

2017 14

2016 10

2015 15

2014 11

2013 12

2012 6

2011 8

2010 14

2009 9

2008 7

2007 10

2006 3

2005 1

展开 ︾

关键词

分子对接 2

分子成像 2

分子设计 2

分子诊断 2

合成 2

安全性 2

定点突变 2

微胶囊 2

控制释放 2

有效性 2

模型试验 2

纳米粒子 2

绿色化工 2

Heterodera glycines 1

ATP荧光检测 1

Epianastrephin 1

FDS数值模拟 1

FLT3抑制剂 1

MERS-CoV 1

展开 ︾

检索范围:

排序: 展示方式:

Synthesis of mid-dicarboxy polystyrene by ATRP and formation of ionic-bonded supramolecules

YU Tao, WANG Yun, LU Dairen, BAI Ruke, LU Weiqi

《化学科学与工程前沿(英文)》 2007年 第1卷 第2期   页码 140-145 doi: 10.1007/s11705-007-0026-4

摘要: Dimethyl 4, 6-bis (bromomethyl) isophthalate was synthesized by bromomethylation, oxidation, esterification and bromination of 1, 3-dimethylbenzene. This was used to initiate the atom transfer radical polymerization of styrene successfully. Results showed that the process had some of the good characteristics of controlled/living free radical polymerization. The molecular weight of the obtained polymer increased linearly with monomer conversion, its molecular weight distribution was very narrow, and a linear relationship between ln([]/[]) and polymerization time was found. A well-defined novel structural polystyrene containing two ester groups in the mid-main chain was prepared with controlled molecular weight and narrow polydispersity. The structure of the polymer was confirmed by H-NMR spectra. After being hydrolyzed, dicarboxy polystyrene was obtained and used to form ionic-bonded supramolecules with 1-dodecanamine as a model of the star-shaped supramolecules. The supramolecules formed were characterized by Fourier transform infrared (FTIR) spectrum.

关键词: controlled molecular     conversion     bromination     relationship     isophthalate    

Synthesis and characterization of biocompatible polyurethanes for controlled release of hydrophobic and

Juichen YANG,Hong CHEN,Yuan YUAN,Debanjan SARKAR,Jie ZHENG

《化学科学与工程前沿(英文)》 2014年 第8卷 第4期   页码 498-510 doi: 10.1007/s11705-014-1451-9

摘要: Design of biocompatible and biodegradable polymer systems for sustained and controlled release of bioactive agents is critical for numerous biomedical applications. Here, we designed, synthesized, and characterized four polyurethane carrier systems for controlled release of model drugs. These polyurethanes are biocompatible and biodegradable because they consist of biocompatible poly(ethylene glycol) or poly(caprolactone diol) as soft segment, linear aliphatic hexamethylene diisocyanate or symmetrical aliphatic cyclic dicyclohexylmethane-4,4′-diisocyanate as hard segment, and biodegradable urethane linkage. They were characterized with Fourier transform infrared spectroscopy, atomic force microscope, and differential scanning calorimetry, whereas their degradation behaviors were investigated in both phosphate buffered saline and enzymatic solutions. By tuning polyurethane segments, different release profiles of hydrophobic and hydrophilic drugs were obtained in the absence and presence of enzymes. Such difference in release profiles was attributed to a complex interplay among structure, hydrophobicity, and degradability of polyurethanes, the size and hydrophobicity of drugs, and drug-polymer interactions. Different drug-polyurethane combinations modulated the distribution and location of the drugs in polymer matrix, thus inducing different drug release mechanisms. Our results highlight an important role of segmental structure of the polyurethane as an engineering tool to control drug release.

关键词: phase structure     degradation     polyurethanes     controlled release     drug delivery    

Size-controlled green synthesis of silver nanoparticles assisted by L-cysteine

Wenchao Zhang,Lin Zhang,Yan Sun

《化学科学与工程前沿(英文)》 2015年 第9卷 第4期   页码 494-500 doi: 10.1007/s11705-015-1527-1

摘要: A green and size-controlled synthesis of silver nanoparticles (Ag NPs) in aqueous solution with the assistance of L-cysteine is presented. The size of Ag NPs decreases with the increase of L-cysteine concentration, and thus can be controlled by adjusting L-cysteine concentration. TEM analysis shows that Ag NPs with an average size of 3 nm can be produced in the presence of 1.0 mmol/L L-cysteine, about one sixth of the size of Ag NPs obtained in the absence of L-cysteine (17 nm). The as-synthesized silver colloidal solution is stable and can be stored at room temperature for at least two months without any precipitation. This L-cysteine assisted method is simple, feasible and efficient, and would facilitate the production and application of Ag NPs.

关键词: nanoparticles     silver     L-cysteine     size distribution     synthesis    

Analysis and stabilization control of a voltage source controlled wind farm under weak grid conditions

《能源前沿(英文)》 2022年 第16卷 第6期   页码 943-955 doi: 10.1007/s11708-021-0793-5

摘要: This paper investigates and discusses the interaction stability issues of a wind farm with weak grid connections, where the wind turbines (WTs) are controlled by a new type of converter control strategy referred to as the voltage source (VS) control. The primary intention of the VS control method is to achieve the high-quality inertial response capability of a single WT. However, when it is applied to multiple WTs within a wind farm, its weak-grid performance regarding the stability remains concealed and needs to be clarified. To this end, a frequency domain model of the wind farm under the VS control is first developed. Based on this model and the application of a stability margin quantification index, not only the interactions between the wind farm and the weak grid but also those among WTs will be systematically assessed in this paper. A crucial finding is that the inertial response of VS control has negative impacts on the stability margin of the system, and the dominant instability mode is more related to the interactions among the WTs rather than the typical grid-wind farm interaction. Based on this knowledge, a stabilization control strategy is then proposed, aiming for stability improvements of VS control while fulfilling the demand of inertial responses. Finally, all the results are verified by time-domain simulations in power systems computer aided design/electromagnetic transients including DC(PSCAD/EMTDC).

关键词: weak grids     voltage source (VS) control     wind turbine (WT)     stabilization control     wind farm     inertial response    

Chinese medicine patterns on patients with pneumoconiosis: a pilot double-blind, randomized, and placebo-controlled

《医学前沿(英文)》 2022年 第16卷 第5期   页码 736-744 doi: 10.1007/s11684-021-0870-5

摘要: Effective therapy options for pneumoconiosis are lacking. Traditional Chinese medicine (TCM) presents a favorable prospect in the treatment of pneumoconiosis. A pilot study on TCM syndrome differentiation can evaluate the clinical efficacy and safety of TCM and lay a foundation for further clinical research. A double-blind, randomized, and placebo-controlled trial was conducted for 24 weeks, in which 96 patients with pneumoconiosis were randomly divided into the control and treatment groups. Symptomatic treatment was conducted for the two groups. The treatment group was treated with TCM syndrome differentiation, and the control group was treated with placebo. The primary outcomes were the six-minute walking distance (6MWD) and the St. George Respiratory Questionnaire (SGRQ) score. The secondary outcomes were the modified British Medical Research Council Dyspnea Scale (mMRC), Chronic Obstructive Pulmonary Disease Assessment Test (CAT), Hospital Anxiety and Depression Scale (HADS), and pulmonary function. Only 83 patients from the 96 patients with pneumoconiosis finished the study. For the primary outcome, compared with the control groups, the treatment group showed a significantly increased 6MWD (407.90 m vs. 499.51 m; 95% confidence interval (CI) 47.25 to 135.97; P <0.001) and improved SGRQ total score (44.48 vs. 25.67; 95% CI −27.87 to −9.74; P <0.001). The treatment group also significantly improved compared with the control group on mMRC score (1.4 vs. 0.74; 95% CI −1.08 to −0.23; P =0.003), CAT score (18.40 vs. 14.65; 95% CI −7.07 to −0.43; P =0.027), and the total symptom score (7.90 vs. 5.14; 95% CI −4.40 to −1.12; P <0.001). No serious adverse events occurred. This study showed that TCM syndrome differentiation and treatment had a favorable impact on the exercise endurance and quality of life of patients with pneumoconiosis.

关键词: pneumoconiosis     randomized controlled trials     traditional Chinese medicine    

Applications of thermostatically controlled loads for demand response with the proliferation of variable

Meng SONG, Wei SUN

《能源前沿(英文)》 2022年 第16卷 第1期   页码 64-73 doi: 10.1007/s11708-021-0732-5

摘要: More flexibility is desirable with the proliferation of variable renewable resources for balancing supply and demand in power systems. Thermostatically controlled loads (TCLs) attract tremendous attentions because of their specific thermal inertia capability in demand response (DR) programs. To effectively manage numerous and distributed TCLs, intermediate coordinators, e.g., aggregators, as a bridge between end users and dispatch operators are required to model and control TCLs for serving the grid. Specifically, intermediate coordinators get the access to fundamental models and response modes of TCLs, make control strategies, and distribute control signals to TCLs according the requirements of dispatch operators. On the other hand, intermediate coordinators also provide dispatch models that characterize the external characteristics of TCLs to dispatch operators for scheduling different resources. In this paper, the bottom-up key technologies of TCLs in DR programs based on the current research have been reviewed and compared, including fundamental models, response modes, control strategies, dispatch models and dispatch strategies of TCLs, as well as challenges and opportunities in future work.

关键词: thermostatically controlled load     demand response     renewable energy     power system operation    

All-in-one functional supramolecular nanoparticles based on pillar[5]arene for controlled generation,

《化学科学与工程前沿(英文)》 2023年 第17卷 第3期   页码 307-313 doi: 10.1007/s11705-022-2216-5

摘要: The storage and controlled release of singlet oxygen (1O2) have attracted increasing attention due to the wide application and microsecond lifetime of 1O2 in water. Herein we provide an integrated nanoplatform consisting of a diphenylanthracene derivative, a water-soluble pillar[5]arene and a photosensitizer tetrakis(4-hydroxyphenyl)porphyrin (TPP), that may provide the controlled generation, storage and release of singlet oxygen. We design a new diphenylanthracene derivative with two trimethylammonium bromide groups on both ends that can be well recognized by the pillar[5]arene. The formed nanocarriers can be used to load TPP through their supramolecular self-assembly. The resulting nanoparticles show good water-solubility and uniform spherical morphology. After laser irradiation (660 nm), the nanoparticles exhibit excellent ability for the generation and storage of 1O2. When the irradiated nanoparticles are heated above 80 °C, 1O2 can be released from the system. Therefore, in this paper we pioneer the use of noncovalent interaction to integrate the diphenylanthracene derivatives and photosensitizers into one functional system, which provides a new strategy for the controlled generation, storage and release of singlet oxygen. We believe this groundbreaking strategy will have a great potential in providing necessary amounts of 1O2 for the photodynamic therapy of tumors in dark.

关键词: storage and controlled release of singlet oxygen     supramolecular nanoparticles     noncovalent interactions     pillararenes     diphenylanthracene     photosensitizers    

Special issue on “Molecular Sensors and Molecular Logic Gates”

Luling Wu , Tony D. James

《化学科学与工程前沿(英文)》 2022年 第16卷 第1期   页码 1-3 doi: 10.1007/s11705-021-2134-y

Design of bio-oil additives via molecular signature descriptors using a multi-stage computer-aided molecular

《化学科学与工程前沿(英文)》 2022年 第16卷 第2期   页码 168-182 doi: 10.1007/s11705-021-2056-8

摘要: Direct application of bio-oil from fast pyrolysis as a fuel has remained a challenge due to its undesirable attributes such as low heating value, high viscosity, high corrosiveness and storage instability. Solvent addition is a simple method for circumventing these disadvantages to allow further processing and storage. In this work, computer-aided molecular design tools were developed to design optimal solvents to upgrade bio-oil whilst having low environmental impact. Firstly, target solvent requirements were translated into measurable physical properties. As different property prediction models consist different levels of structural information, molecular signature descriptor was used as a common platform to formulate the design problem. Because of the differences in the required structural information of different property prediction models, signatures of different heights were needed in formulating the design problem. Due to the combinatorial nature of higher-order signatures, the complexity of a computer-aided molecular design problem increases with the height of signatures. Thus, a multi-stage framework was developed by developing consistency rules that restrict the number of higher-order signatures. Finally, phase stability analysis was conducted to evaluate the stability of the solvent-oil blend. As a result, optimal solvents that improve the solvent-oil blend properties while displaying low environmental impact were identified.

关键词: computer-aided molecular design     bio-oil additives     molecular signature descriptor    

Correction to: Highly degradable chitosan-montmorillonite (MMT) nanocomposite hydrogel for controlled

《环境科学与工程前沿(英文)》 2023年 第17卷 第8期 doi: 10.1007/s11783-023-1704-2

Progress on molecular biomarkers and classification of malignant gliomas

null

《医学前沿(英文)》 2013年 第7卷 第2期   页码 150-156 doi: 10.1007/s11684-013-0267-1

摘要:

Gliomas are the most common primary intracranial tumors in adults. Anaplastic gliomas (WHO grade III) and glioblastomas (WHO grade IV) represent the major groups of malignant gliomas in the brain. Several diagnostic, predictive, and prognostic biomarkers for malignant gliomas have been reported over the last few decades, and these markers have made great contributions to the accuracy of diagnosis, therapeutic decision making, and prognosis of patients. However, heterogeneity in patient outcomes may still be observed, which highlights the insufficiency of a classification system based purely on histopathology. Great efforts have been made to incorporate new information about the molecular landscape of gliomas into novel classifications that may potentially guide treatment. In this review, we summarize three distinctive biomarkers, three most commonly altered pathways, and three classifications based on microarray data in malignant gliomas.

关键词: malignant glioma     molecular biomarker     IDH1     MGMT     molecular classification    

Molecular classification and molecular targeted therapy of cancer

null

《医学前沿(英文)》 2013年 第7卷 第2期   页码 147-149 doi: 10.1007/s11684-013-0274-2

Semi-solid materials for controlled release drug formulation: current status and future prospects

Michelle TRAN,Chun WANG

《化学科学与工程前沿(英文)》 2014年 第8卷 第2期   页码 225-232 doi: 10.1007/s11705-014-1429-7

摘要: Semi-solid materials represent an important category of inactive ingredients (excipients) of pharmaceutical products. Here we review several common semi-solid polymers currently used in the controlled release formulations of many drugs. These polymers are selected based on their importance and broad scope of application in FDA-approved drug products and include several polysaccharides (cellulose, starch, chitosan, alginate) and carbomers, a group of mucoadhesive synthetic polymers. Glyceride-based polymers used in self-emulsifying drug delivery systems (SEDDS) will also be discussed for its importance in formulating poorly water-soluble drugs. Unique features and advantages of each type of semi-solid materials are discussed and examples of their use in oral delivery of drugs are provided. Finally, future prospects of developing new and better semi-solid excipients are discussed with the objective of facilitating clinical translation.

关键词: controlled release     drug delivery     semi-solids     polymer     excipient    

Optimization of fuel supply map during starting process of electronic controlled diesel engine

LIANG Jinguang, YU Xiumin, GAO Yue, WANG Yunkai, YU Hongyang, Gong Baoli

《能源前沿(英文)》 2008年 第2卷 第4期   页码 410-415 doi: 10.1007/s11708-008-0080-8

摘要: Tests were conducted to study influence of fuel supply map during the starting process of an electronic controlled diesel engine using an electronic controlled diesel engine which was made up of a CA498Z diesel engine, a VP37 electronic controlled distributor injection pump management system and a VS100 calibration system. The calibration process of starting fuel supply map was educed under the principle of low HC emission and rapid starting velocity. The calibration methods of starting fuel supply map were obtained.

关键词: supply     management     CA498Z     process     controlled distributor    

EEG controlled neuromuscular electrical stimulation of the upper limb for stroke patients

Hock Guan TAN, Cheng Yap SHEE, Keng He KONG, Cuntai GUAN, Wei Tech ANG

《机械工程前沿(英文)》 2011年 第6卷 第1期   页码 71-81 doi: 10.1007/s11465-011-0207-1

摘要:

This paper describes the Brain Computer Interface (BCI) system and the experiments to allow post-acute (<3 months) stroke patients to use electroencephalogram (EEG) to trigger neuromuscular electrical stimulation (NMES)-assisted extension of the wrist/fingers, which are essential pre-requisites for useful hand function. EEG was recorded while subjects performed motor imagery of their paretic limb, and then analyzed to determine the optimal frequency range within the -rhythm, with the greatest attenuation. Aided by visual feedback, subjects then trained to regulate their -rhythm EEG to operate the BCI to trigger NMES of the wrist/finger. 6 post-acute stroke patients successfully completed the training, with 4 able to learn to control and use the BCI to initiate NMES. This result is consistent with the reported BCI literacy rate of healthy subjects. Thereafter, without the loss of generality, the controller of the NMES is developed and is based on a model of the upper limb muscle (biceps/triceps) groups to determine the intensity of NMES required to flex or extend the forearm by a specific angle. The muscle model is based on a phenomenological approach, with parameters that are easily measured and conveniently implemented.

关键词: brain computer interface     neuromuscular electrical stimulation     stroke     musculoskeletal modeling    

标题 作者 时间 类型 操作

Synthesis of mid-dicarboxy polystyrene by ATRP and formation of ionic-bonded supramolecules

YU Tao, WANG Yun, LU Dairen, BAI Ruke, LU Weiqi

期刊论文

Synthesis and characterization of biocompatible polyurethanes for controlled release of hydrophobic and

Juichen YANG,Hong CHEN,Yuan YUAN,Debanjan SARKAR,Jie ZHENG

期刊论文

Size-controlled green synthesis of silver nanoparticles assisted by L-cysteine

Wenchao Zhang,Lin Zhang,Yan Sun

期刊论文

Analysis and stabilization control of a voltage source controlled wind farm under weak grid conditions

期刊论文

Chinese medicine patterns on patients with pneumoconiosis: a pilot double-blind, randomized, and placebo-controlled

期刊论文

Applications of thermostatically controlled loads for demand response with the proliferation of variable

Meng SONG, Wei SUN

期刊论文

All-in-one functional supramolecular nanoparticles based on pillar[5]arene for controlled generation,

期刊论文

Special issue on “Molecular Sensors and Molecular Logic Gates”

Luling Wu , Tony D. James

期刊论文

Design of bio-oil additives via molecular signature descriptors using a multi-stage computer-aided molecular

期刊论文

Correction to: Highly degradable chitosan-montmorillonite (MMT) nanocomposite hydrogel for controlled

期刊论文

Progress on molecular biomarkers and classification of malignant gliomas

null

期刊论文

Molecular classification and molecular targeted therapy of cancer

null

期刊论文

Semi-solid materials for controlled release drug formulation: current status and future prospects

Michelle TRAN,Chun WANG

期刊论文

Optimization of fuel supply map during starting process of electronic controlled diesel engine

LIANG Jinguang, YU Xiumin, GAO Yue, WANG Yunkai, YU Hongyang, Gong Baoli

期刊论文

EEG controlled neuromuscular electrical stimulation of the upper limb for stroke patients

Hock Guan TAN, Cheng Yap SHEE, Keng He KONG, Cuntai GUAN, Wei Tech ANG

期刊论文