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41.
Xu Yifan Zhang Hehe Ding Tangjing Tian Ruiqi Sun Dongmei Wang Ming-Sheng Zhou Xiaosi 《中国科学:化学(英文版)》2022,65(9):1807-1816
Science China Chemistry - Due to their enormous potential for large-scale energy storage, rechargeable potassium-ion batteries have been widely researched and developed. However, the drastic volume... 相似文献
42.
Journal of Applied Spectroscopy - The concentration of heavy metals in drinking water is an important standard for water quality evaluation and water pipeline corrosion detection. This research... 相似文献
43.
Dong-Yang Liu 《中国物理 B》2022,31(12):128104-128104
Regulation of oxygen on properties of moderately boron-doped diamond films is fully investigated. Results show that, with adding a small amount of oxygen (oxygen-to-carbon ratio < 5.0%), the crystal quality of diamond is improved, and a suppression effect of residual nitrogen is observed. With increasing ratio of O/C from 2.5% to 20.0%, the hole concentration is firstly increased then reduced. This change of hole concentration is also explained. Moreover, the results of Hall effect measurement with temperatures from 300 K to 825 K show that, with adding a small amount of oxygen, boron and oxygen complex structures (especially B3O and B4O) are formed and exhibit as shallow donor in diamond, which results in increase of donor concentration. With further increase of ratio of O/C, the inhibitory behaviors of oxygen on boron leads to decrease of acceptor concentration (the optical emission spectroscopy has shown that it is decreased with ratio of O/C more than 10.0%). This work demonstrates that oxygen-doping induced increasement of the crystalline and surface quality could be restored by the co-doping with oxygen. The technique could achieve boron-doped diamond films with both high quality and acceptable hole concentration, which is applicable to electronic level of usage. 相似文献
44.
《中国化学快报》2022,33(4):1889-1894
Permeation enhancers (PEs), such as N-[8-(2-hydroxybenzoyl)amino]-caprylate (SNAC), have been reported to improve the oral absorption of various macromolecules. However, the bioavailabilities of these formulations are quite low and variable due to the influences of enzymes, pH and other gastrointestinal barriers. In this study, we revealed that SNAC could interact with insulin to form tight complexes in a specific concentration (insulin ≥ 40 µg/mL)-, ratio (SNAC/insulin ≥ 20:1)- and pH (≥ 6.8)-dependent manner, thus contributing to a significantly high efficacy of oral insulin delivery. Specifically, absorption mechanism studies revealed that the SNAC/insulin complexes were internalized into the cells by passive diffusion and remained intact when transported in the cytosol. Furthermore, the complexes accelerated the exocytosis of insulin to the basolateral side, thereby enhancing its intestinal mucosal permeability. Eudragit? S100-entrapped SNAC/insulin microspheres were then prepared and exhibited an apparent permeability coefficient (Papp) that was 6.6-fold higher than that of the insulin solution. In diabetic rats, hypoglycemic activity was sustained for more than 10 h after the microspheres were loaded into enteric-coated capsules. Further pharmacokinetic studies revealed an approximately 6.3% oral bioavailability in both the fasted and fed states, indicating a negligible food effect. Collectively, this study provides insight into the interaction between PEs and payloads and presents an SNAC-based oral insulin delivery system that has high oral bioavailability and patient-friendly medication guidance. 相似文献
45.
46.
Si-Yang Feng Tao Zheng Ai-Jing Sun Zuo-Xiang Wang 《Molecular Crystals and Liquid Crystals》2019,692(1):43-52
AbstractComplexes of [CdL2(NO3)2]·1.5H2O and [Ag2(μ-L)2(NO3)2] were synthesized by the reactions of 2-p-methylphenyl-5-(2-pyridyl)-1,3,4-thiadiazole (L) with Cd(NO3)2·4H2O and AgNO3, respectively. Their structures were determined by single crystal X-ray diffraction. The photophysical property and thermal stability were characterized by FT???IR, UV???Vis absorption, fluorescence, and thermogravimetric analysis (TGA). Both complexes belong to the triclinic system with space group p???1. The central metal of [CdL2(NO3)2]·1.5H2O has a distorted octahedral geometry [CdN4O2], while two central Ag(I) atoms of [Ag2(μ-L)2(NO3)2] exhibit distorted tetrahedral geometries [AgN3O]. 相似文献
47.
BackgroundPhosphoinositide-3-kinase Delta (PI3Kδ) plays a key role in B-cell signal transduction and inhibition of PI3Kδ is confirmed to have clinical benefit in certain types of activation of B-cell malignancies. Virtual screening techniques have been used to discover new molecules for developing novel PI3Kδ inhibitors with little side effects.MethodComputer aided drug design method were used to rapidly screen optimal PI3Kδ inhibitors from the Asinex database. Virtual screening based molecular docking was performed to find novel and potential lead compound targeting PI3Kδ, at first. Subsequently, drug likeness studies were carried out on the retrieved hits to evaluate and analyze their drug like properties such as absorption, distribution, metabolism, excretion, and toxicity (ADMET) for toxicity prediction. Three least toxic compounds were selected for the molecular dynamics (MD) simulations for 30 ns in order to validate its stability inside the active site of PI3Kδ receptor.ResultsBased on the present in silico analysis, two molecules have been identified which occupied the same binding pocket confirming the selection of active site. ASN 16296138 (Glide score: −12.175 kcal/mol, cdocker binding energy: −42.975 kcal/mol and ΔGbind value: −90.457 kcal/mol) and BAS 00227397 (Glide score: −10.988 kcal/mol, cdocker binding energy: −39.3376 kcal/mol and ΔGbind value: −81.953 kcal/mol) showed docking affinities comparatively much stronger than those of already reported known inhibitors against PI3Kδ. These two ligand’s behaviors also showed consistency during the simulation of protein-ligand complexes for 30000 ps respectively, which is indicative of its stability in the receptor pocket.ConclusionCompound ASN 16296138 and BAS 00227397 are potential candidates for experimental validation of biological activity against PI3Kδ in future drug discovery studies. This study smoothes the path for the development of novel leads with improved binding properties, high drug likeness, and low toxicity to humans for the treatment of cancer. 相似文献
48.
Jiang Xiao-yan Lu Qiang Hu Bin Chen Deng-yu Liu Ji Dong Chang-qing 《Journal of Thermal Analysis and Calorimetry》2019,137(1):151-160
Journal of Thermal Analysis and Calorimetry - In order to understand the catalytic effects of inherent inorganic elements in biomass on the pyrolysis mechanism of lignin, density functional theory... 相似文献
49.
In this study, a tubular radon removal device and a movable one were prepared and investigated. The tubular radon removal device in an air conditioning return air system reduced the radon progeny by more than 84%. The radon progeny concentration reached equilibrium after 4 h when it was used only for a ventilation at the rate of 10 h−1. Radon progeny removal efficiency was above 95% for the movable radon removal device, when the ventilation rate was 17 h−1. The results showed that the radon removal devices can effectively remove the radon progeny in the air.
相似文献50.
Pathogen–host interactions are very important to figure out the infection process at the molecular level, where pathogen proteins physically bind to human proteins to manipulate critical biological processes in the host cell. Data scarcity and data unavailability are two major problems for computational approaches in the prediction of pathogen–host interactions. Developing a computational method to predict pathogen–host interactions with high accuracy, based on protein sequences alone, is of great importance because it can eliminate these problems. In this study, we propose a novel and robust sequence based feature extraction method, named Location Based Encoding, to predict pathogen–host interactions with machine learning based algorithms. In this context, we use Bacillus Anthracis and Yersinia Pestis data sets as the pathogen organisms and human proteins as the host model to compare our method with sequence based protein encoding methods, which are widely used in the literature, namely amino acid composition, amino acid pair, and conjoint triad. We use these encoding methods with decision trees (Random Forest, j48), statistical (Bayesian Networks, Naive Bayes), and instance based (kNN) classifiers to predict pathogen–host interactions. We conduct different experiments to evaluate the effectiveness of our method. We obtain the best results among all the experiments with RF classifier in terms of F1, accuracy, MCC, and AUC. 相似文献