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1. Chemical constituents from Scutellaria hainanensis C. Y. Wu

Author:
Bai, Meng; Zheng, Cai-Juan; Wu, Shou-Yuan; Chen, Guang-Ying; Song, Xiao-Ping; Han, Chang-Ri
Source:
Biochemical systematics and ecology 2019 v.82 pp. 1-12
ISSN:
0305-1978
Subject:
chemical composition,   etc   ; Scutellaria; chemotaxonomy; flavonoids; glycosides; phenylpropanoids;     Show all 6 Subjects
Abstract:
... Seventeen compounds were obtained from the extract of the whole plant of Scutellaria hainanensis C. Y. Wu. Including eleven flavonoids (1–4 and 7–13), two phenylpropanoids (16 and 17), one pyridinium derivative (5), one ester (6), one phenolic derivative (14), and one lignanoid (15). Compound 5 was a synthetic intermediate, newly identified as a natural product. The chemotaxonomic relationship bet ...
DOI:
10.1016/j.bse.2018.10.007

2. Constitutive properties and plastic instabilities in the heat-affected zones of advanced high-strength steel spot welds

Author:
Rezayat, H.; Ghassemi-Armaki, H.; Bhat, S. P.; Sriram, S.; Babu, S. S.
Source:
Journal of materials science 2019 v.54 no.7 pp. 5825-5843
ISSN:
0022-2461
Subject:
chemical composition,   etc   ; digital images; microstructure; steel; temperature; tempering; tensile strength;     Show all 7 Subjects
Abstract:
... Recent publications have shown that the load-bearing capability of advanced high-strength steel (AHSS) spot welds do not scale linearly with the tensile strength of the base metal. Although this unexpected degradation of welds has been linked to the tempering of the martensite phase in the heat-affected zone (HAZ), the detailed elastic–plastic stress–strain behavior in different regions of the HAZ ...
DOI:
10.1007/s10853-018-03276-9

3. Equiaxial nano-crystals Nb3Al superconductor prepared by optimized mechanically alloying

Author:
Zhang, Wenjie; Li, Pingyuan; Zou, Xiaofeng; Yu, Zhou; Yang, Xinsheng; Pan, Xifeng; Zhao, Yong; Zhang, Yong
Source:
Journal of materials science 2019 v.54 no.6 pp. 5022-5031
ISSN:
0022-2461
Subject:
chemical composition,   etc   ; magnetic fields; microstructure; milling; nanocrystals; superconductivity; temperature;     Show all 7 Subjects
Abstract:
... The influence of the original nominal chemical composition, milling time, sintering temperature and holding time was studied systematically on the phase formation, microstructure and superconductivity of mechanically alloyed Nb₃Al. By optimizing the process, we have successfully prepared high-performance Nb₃Al superconductor. Samples with original nominal composition of Nb-27 at.%Al were milled fo ...
DOI:
10.1007/s10853-018-2918-8

4. Mechanisms of temper embrittlement and recovery in cast HY-80 high-strength low-alloy steel

Author:
Draper, M.; Ankem, S.
Source:
Journal of materials science 2019 v.54 no.3 pp. 2601-2611
ISSN:
0022-2461
Subject:
chemical composition,   etc   ; carbides; carbon; heat treatment; phosphorus; steel; temperature;     Show all 7 Subjects
Abstract:
... To better understand the mechanisms and rate of temper embrittlement in cast HY-80 high-strength low-alloy steel, samples were subjected to embrittlement and recovery treatments after a typical industrial heat treatment. The embrittlement rate was studied between 315 and 565 °C at varied logarithmic time intervals up to 10000 min. The embrittlement recovery rate was studied between 593 and 704 °C ...
DOI:
10.1007/s10853-018-2973-1

5. Highlighting IR Spectrochemical Imaging of the Retina

Author:
Aboualizadeh, Ebrahim; Hirschmugl, Carol J.
Source:
Trends in biochemical sciences 2018 v.43 no.9 pp. 650-653
ISSN:
0968-0004
Subject:
chemical composition,   etc   ; image analysis; retina;     Show all 3 Subjects
Abstract:
... An emerging application of mid-IR spectrochemical imaging of the retina is its utility in studying the highly localized biomolecular alterations in the chemistry of retinal cell layers associated with several pathological conditions. Spatially resolved IR images highlight simultaneous chemical composition of the entire span of the retina in a label-free manner. ...
DOI:
10.1016/j.tibs.2018.04.005

6. A theoretical study on the activation of insoluble particles in atmospheric conditions

Author:
Lazaridis, Mihalis
Source:
Atmospheric research 2019 v.218 pp. 306-314
ISSN:
0169-8095
Subject:
chemical composition,   etc   ; aerosols; ambient temperature; models; particle size; probability; sulfuric acid; vapors;     Show all 8 Subjects
Abstract:
... A theoretical analysis for the description of insoluble particles activation in the atmosphere has been performed using as framework the classical theory of heterogeneous nucleation. In the current work a model for heterogeneous nucleation for one-component and two-component gaseous systems was presented taking into account the process of surface diffusion during nucleating embryo formation. The t ...
DOI:
10.1016/j.atmosres.2018.12.013

7. Effect of flow rate on detection limit of particle size for a steam-based aerosol collector

Author:
Hsiao, Ta-Chih; Engling, Guenter; Chang, Po-Yang; Chang, Po-Kai; Chuang, Ming-Tung
Source:
Atmospheric environment 2019 v.202 pp. 160-166
ISSN:
1352-2310
Subject:
chemical composition,   etc   ; aerosols; chemical analysis; chemical concentration; detection limit; droplets; guidelines; particle size; particulates; samplers; steam;     Show all 11 Subjects
Abstract:
... A custom-built steam-based aerosol collector (SBAC) was developed to improve the detection limits in aerosol chemical analysis. The SBAC was coupled with wet chemical analytical instruments to characterize the chemical composition of ambient particulate matter with high-time resolution. The particulate matter was mixed with a jet of steam and formed large droplets because of the supersaturation co ...
DOI:
10.1016/j.atmosenv.2019.01.014

8. Core-shell FeCo@carbon nanoparticles encapsulated in polydopamine-derived carbon nanocages for efficient microwave absorption

Author:
Wang, Fengyuan; Wang, Na; Han, Xijiang; Liu, Dawei; Wang, Yahui; Cui, Liru; Xu, Ping; Du, Yunchen
Source:
Carbon 2019 v.145 pp. 701-711
ISSN:
0008-6223
Subject:
chemical composition,   etc   ; alloys; carbon; coatings; dopamine; magnetism; microstructure; nanoparticles; polymerization; pyrolysis;     Show all 10 Subjects
Abstract:
... Rational manipulation on chemical composition and microstructure is evolving as a powerful approach to reinforce the electromagnetic (EM) functions of magnetic carbon-based composites. With FeCo Prussian blue analogs (FeCo PBAs) as the nucleation sites, we conduct the polymerization of dopamine (DA) on their surface and then convert the precursor into desirable FeCo alloy/carbon composites. PDA co ...
DOI:
10.1016/j.carbon.2019.01.082

9. Non-targeted metabolomics reveals distinct chemical compositions among different grades of Bai Mudan white tea

Author:
Yue, Wenjie; Sun, Weijiang; Rao, R. Shyama Prasad; Ye, Naixing; Yang, Zhenbiao; Chen, Mingjie
Source:
Food chemistry 2019 v.277 pp. 289-297
ISSN:
0308-8146
Subject:
chemical composition,   etc   ; ionization; mass spectrometry; metabolites; metabolomics; models; multivariate analysis; ultra-performance liquid chromatography; white tea;     Show all 9 Subjects
Abstract:
... So far, the chemical quality of different grades of white tea has largely remained unexplored. The objective of this study was to establish a model for quality evaluation of different grades of Bai Mudan white tea. We applied non-targeted ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry in combination with multivariate analysis and analyzed four different grades ...
DOI:
10.1016/j.foodchem.2018.10.113

10. Investigating chemical, physical and mechanical properties of eco-cement produced using dry sewage sludge and traditional raw materials

Author:
Rezaee, Fahimeh; Danesh, Shahnaz; Tavakkolizadeh, Mohammadreza; Mohammadi-Khatami, Mohammad
Source:
Journal of cleaner production 2019 v.214 pp. 749-757
ISSN:
0959-6526
Subject:
chemical composition,   etc   ; cement; durability; fineness; mechanical properties; raw materials; sewage sludge; specific gravity;     Show all 8 Subjects
Abstract:
... This work was performed to investigate the effect of using dry municipal sewage sludge as one of the raw materials in Portland cement production on the mechanical and durability properties of an environmentally sustainable cement (eco-cement). The specimens were prepared as one control and four different replacement level of dry sewage sludge as partial substitute of traditional raw materials (5.0 ...
DOI:
10.1016/j.jclepro.2018.12.153

11. Effects of smoking or baking procedures during sausage processing on the formation of heterocyclic amines measured using UPLC-MS/MS

Author:
Yang, Diaodiao; He, Zhiyong; Gao, Daming; Qin, Fang; Deng, Shaolin; Wang, Peng; Xu, Xinglian; Chen, Jie; Zeng, Maomao
Source:
Food chemistry 2019 v.276 pp. 195-201
ISSN:
0308-8146
Subject:
chemical composition,   etc   ; baking; color; heterocyclic amines; pH; principal component analysis; smoked sausage; tandem mass spectrometry; temperature;     Show all 9 Subjects
Abstract:
... We used an UPLC-MS/MS method to investigate the effects of smoking or baking on the formation of heterocyclic amines (HAs) in sausage processing. We used principal component analysis (PCA) to differentiate the chemical composition, pH and colour of the processed sausages. We detected and quantified eight types of HAs (PhIP, DMIP, Phe-P-1, IQ[4,5-b], 7,8-DiMeIQx, AαC, harman and norharman) in sausa ...
DOI:
10.1016/j.foodchem.2018.09.160

12. Effect of wet flue gas desulfurization (WFGD) on fine particle (PM2.5) emission from coal-fired boilers

Author:
Yao, Sen; Cheng, Shuiyuan; Li, Jianbing; Zhang, Hanyu; Jia, Jia; Sun, Xiaowei
Source:
Journal of environmental sciences (China) 2019 v.77 pp. 32-42
ISSN:
1001-0742
Subject:
chemical composition,   etc   ; boilers; calcium; cations; coal; flue gas desulfurization; magnesium; particulates; sodium; sulfates; water solubility; China;     Show all 12 Subjects
Abstract:
... In this study, the characteristics of fine particles before and after wet flue gas desulfurization (WFGD) in three coal-fired heating boilers in northern China were investigated by using a dilution-based emission sampling experimental system. The influences of the WFGD process on the mass and number concentrations as well as the chemical composition of fine particles were analyzed. The removal eff ...
DOI:
10.1016/j.jes.2018.05.005

13. Identification and quantification of electronic cigarette exhaled aerosol residue chemicals in field sites

Author:
Khachatoorian, Careen; Jacob, Peyton; Sen, Amy; Zhu, Yifang; Benowitz, Neal L.; Talbot, Prue
Source:
Environmental research 2019 v.170 pp. 351-358
ISSN:
0013-9351
Subject:
chemical composition,   etc   ; aerosols; air flow; cotton; electronic equipment; environmental hazards; fabrics; human resources; nicotine; nitrosamines; polyesters;     Show all 11 Subjects
Abstract:
... Electronic cigarette (EC) users may exhale large clouds of aerosol that can settle on indoor surfaces forming ECEAR (EC exhaled aerosol residue). Little is known about the chemical composition or buildup of this residue.Our objective was to identify and quantify ECEAR chemicals in two field sites: an EC user's living room and a multi-user EC vape shop.We examined the buildup of ECEAR in commonly u ...
DOI:
10.1016/j.envres.2018.12.027

14. The effect of composition and morphological features on the striation of .22LR ammunition

Author:
Manzalini, Valentina; Frisia, Michele; Casolari, Monica; Causin, Valerio
Source:
Forensic science international 2019 v.296 pp. 9-14
ISSN:
0379-0738
Subject:
chemical composition,   etc   ; chemical analysis; crime; light microscopy; models; nondestructive methods; scanning electron microscopy;     Show all 7 Subjects
Abstract:
... In this paper, the effect of the chemical composition of .22LR bullets was studied and correlated to the extent and quality of the markings left after shooting them with the same gun. Scanning electron microscopy and optical comparator microscopy equipped with 3D and profilometry modules were used as non destructive techniques with two main purposes. The first is to assist the firearm examiner in ...
DOI:
10.1016/j.forsciint.2018.12.014

15. The genus Ferula: Ethnobotany, phytochemistry and bioactivities – A review

Author:
Mohammadhosseini, Majid; Venditti, Alessandro; Sarker, Satyajit D.; Nahar, Lutfun; Akbarzadeh, Abolfazl
Source:
Industrial crops and products 2019 v.129 pp. 350-394
ISSN:
0926-6690
Subject:
chemical composition,   etc   ; Ferula; bioactive properties; chemotaxonomy; coumarins; essential oils; ethnobotany; glycosides; secondary metabolites; sesquiterpenoids;     Show all 10 Subjects
Abstract:
... This study aims to provide a comprehensive overview of the medicinal, folkloric and traditional culinary uses of Ferula species, related products and extracts in different countries together with the description of recently isolated new components and the related bioactivities. The phytochemical composition of the essential oils (EOs), oleo-gum-resin (OGR) and the non-volatile fractions obtained f ...
DOI:
10.1016/j.indcrop.2018.12.012

16. Impact of emissions from the Ports of Los Angeles and Long Beach on the oxidative potential of ambient PM0.25 measured across the Los Angeles County

Author:
Mousavi, Amirhosein; Sowlat, Mohammad H.; Hasheminassab, Sina; Polidori, Andrea; Shafer, Martin M.; Schauer, James J.; Sioutas, Constantinos
Source:
The Science of the total environment 2019 v.651 pp. 638-647
ISSN:
0048-9697
Subject:
chemical composition,   etc   ; aerosols; emissions; macrophages; monitoring; particulates; regression analysis; ships; toxicity;     Show all 9 Subjects
Abstract:
... In this study, weekly samples of ambient PM0.25 (particulate matter with an aerodynamic diameter <0.25 μm) were collected in three contrasting locations, including central Los Angeles (USC), north Long Beach (NLB), and the Port of Long Beach (PRT), during June and July of 2017 to evaluate the chemical composition of ambient PM0.25 and identify the sources that contribute to the oxidative potential ...
DOI:
10.1016/j.scitotenv.2018.09.155

17. Analysis of chemical constituents from Polygonatum cyrtonema after “Nine-Steam-Nine-Bask” processing

Author:
Wang, Wen-Xiang; Zhang, Xian; Dabu, Xi-La-Tu; He, Juan; Yang, Sheng-Chao; Chen, Jun-Wen; Fan, Wei; Zhang, Guang-Hui; Ai, Hong-Lian; Hai, Mei-Rong
Source:
Phytochemistry letters 2019 v.29 pp. 35-40
ISSN:
1874-3900
Subject:
chemical composition,   etc   ; Polygonatum cyrtonema; anti-inflammatory activity; glucose; inhibitory concentration 50; nitric oxide; spectral analysis;     Show all 7 Subjects
Abstract:
... Seven new compounds, known as polygonatine N1‒N7 (1‒7), and a known compound (8) were isolated from the ‘Nine-Steam-Nine-Bask’ processing product of Polygonatum cyrtonema Hua. The compounds’ structures were determined by spectroscopic analysis. All compounds were tested for dipeptidyl peptidase-4 (DPP-4) inhibition, glucose transport, and anti-inflammatory activities. Compound 8 suppressed NO prod ...
DOI:
10.1016/j.phytol.2018.11.004

18. Brewing with malted barley or raw barley: what makes the difference in the processes?

Author:
Kok, Yee Jiun; Ye, Lijuan; Muller, Jeroen; Ow, Dave Siak-Wei; Bi, Xuezhi
Source:
Applied microbiology and biotechnology 2019 v.103 no.3 pp. 1059-1067
ISSN:
0175-7598
Subject:
chemical composition,   etc   ; barley; beers; brewing; enzymes; malt; malting; malting barley; milling; sugars; yeasts;     Show all 11 Subjects
Abstract:
... Malted barley is the main source for fermentable sugars used by yeasts in the traditional brewing of beers but its use has been increasingly substituted by unmalted barley and other raw grain adjuncts in recent years. The incorporation of raw grains is mainly economically driven, with the added advantage of improved sustainability, by reducing reliance on the malting process and its associated cos ...
DOI:
10.1007/s00253-018-9537-9

19. Chemical composition and water permeability of the cuticular wax barrier in rose leaf and petal: A comparative investigation

Author:
Cheng, Guiping; Huang, Hua; Zhou, Linyan; He, Shenggen; Zhang, Yajun; Cheng, Xing'an
Source:
Plant physiology and biochemistry 2019 v.135 pp. 404-410
ISSN:
0981-9428
Subject:
chemical composition,   etc   ; Rosa chinensis; alkanes; corolla; cultivars; epicuticular wax; leaves; permeability; plant organs; transpiration; waxes;     Show all 11 Subjects
Abstract:
... Cuticular wax is the main transpiration barrier against uncontrolled water loss for all aerial plant organs. This study presents water permeability and chemical composition of the cuticle on the petals and leaves of two cultivars of Rosa chinensis (‘Movie star’ and ‘Tineke’). Numerous cultivar- and organ-specific differences, such as the water permeability and total cuticular wax, were detected am ...
DOI:
10.1016/j.plaphy.2019.01.006

20. On‐vine withering process of ‘Moscato bianco’ grapes: effect of cane‐cut system on volatile composition

Author:
Giacosa, Simone; Giordano, Manuela; Vilanova, Mar; Cagnasso, Enzo; Río Segade, Susana; Rolle, Luca
Source:
Journal of the science of food and agriculture 2019 v.99 no.3 pp. 1135-1144
ISSN:
0022-5142
Subject:
chemical composition,   etc   ; geraniol; glycosylation; grapes; harvest date; linalool; nerol; small fruits; volatile compounds; winemaking;     Show all 10 Subjects
Abstract:
... BACKGROUND: Cane‐cut on‐vine withering is a grape dehydration technique used for dry and sweet wine production. The aim of this work was to study the influence of the cane‐cut technique applied at harvest to Moscato bianco grapes during the on‐vine withering process to produce dehydrated berries with a different chemical composition and a volatile profile. RESULTS: After 24 days of dehydration, an ...
DOI:
10.1002/jsfa.9281