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Triboluminescence (TL) is an optical phenomenon in which light is emitted from the surface of a material when subjected to pressure or shear forces. Due to its potential applications in non-destructive testing, radiation sources, and spectroscopic probes, TL has garnered increasing attention over the past two decades. However, experimental observations in the infrared spectrum remain limited, and its emission mechanism has not yet been fully understood. In this study, significant emission in the near-infrared spectrum was experimentally observed from the tribo-pairs of Cr/YSZ and quartz/YSZ. The results indicate that the Tribo-Induced Near-Infrared Light Emission consists of three peaks, in which the 780 nm peak is related to the electronic transition between the 3d5/2 and 3d3/2 orbitals of Y3+ ions, while the 880 nm and 990 nm peaks can be attributed to hole centers and T-type centers in the intrinsic defects of YSZ, respectively. Additionally, experiments reveal that the Cr/YSZ tribo-pair exhibits a redshift of 11–18 nm at the 780 nm peak compared to the quartz/YSZ tribo-pair. To explain the cause of the redshift phenomenon, X-ray photoelectron spectroscopy and UV-Vis absorption spectroscopy were used to measure the energy level spacing between the 3d5/2 and 3d3/2 orbitals of Y3+ and the bandgap width of YSZ before and after friction, respectively. We found that the bandgap width of the doped YSZ decreases after friction, which is often accompanied by a reduction in the energy level spacing between the 3d5/2 and 3d3/2 orbitals of Y3+. The extent of the reduction in energy level spacing varies with different dopants, leading to the redshift phenomenon. [ABSTRACT FROM AUTHOR]

Biodegradable polymer materials are attractive in various biomedical applications. Herein, we report a block aliphatic copolymer, polycaprolactone-block-polyglycolide (PCL-b-PGA, denoted as PCLGA), and explored the polymer composition effect on the thermal and degradation behaviors. Three copolymers with different PCL/PGA weight ratios were obtained by a two-step ring opening polymerization. The chemical structures and compositions of copolymers were studied by NMR and FT-IR. The thermal behaviors were investigated by DSC and TGA. The in vitro degradation in phosphate buffer saline and in vivo degradation as an implant in rats were evaluated and the hygroscopic rate and polymer weight loss changes were monitored in an eight-week period. PCLGA with a higher PCL composition showed a slower degradation in vitro and in vivo. These PCLGAs with different degradation rates could be used as biomedical implants for potential application in drug delivery and tissue repair. [ABSTRACT FROM AUTHOR]

Under the condition of the same cavity depth, four circular cavity combined filter rods with different cavity diameter were designed, and the influence of cavity diameter on the main physical and chemical indexes and sensory quality of cigarettes was studied. The results showed as follows: the release amounts of total particulate matter, tar and nicotine of circular cavity combined filter cigarettes increased with the increase of cavity diameter, and were higher than those of cigarettes with ordinary cellulose acetate filters. The nicotine interception in ordinary tow segment had little change, while the nicotine interception in the tow segment of the cavity filter rod and the nicotine interception per unit area gradually decreased with the increase of the cavity diameter. With the increase of cavity diameter, the hazard index of combined filter cigarettes increased, and the offset of cigarette hazard index gradually increased. The sensory quality evaluation score of combined filter cigarettes decreased with the increase of the cavity diameter. [ABSTRACT FROM AUTHOR]

In order to establish prediction models for the routine smoke components released from demi-slim cigarettes based on their material parameters, cigarette samples with different material parameters were designed by a central composite design combined with an orthogonal design. Seven prediction equations for the releases of TPM(total particulate matter), tar, nicotine, CO, moisture in mainstream smoke and the open draw resistance and total ventilation rate of the demi-slim cigarettes were established by using linear regression and stepwise regression methods. The optimal models were selected according to the statistical principle of minimum root mean squares error of cross validation (RMSECV) and maximum linearly dependent coefficients between the predicted and measured values. The models were verified with commercial demi-slim cigarettes. The results showed that the average prediction relative deviations of TPM, tar, nicotine, CO and moisture releases, the open draw resistance and the total ventilation rate were 4.0%, 2.1%, 6.0%, 4.5%, 8.3%, 6.6% and 3.2%, respectively, which indicated that the models had good prediction accuracies and suitable applicability for demi-slim cigarette designs with different tobacco blends and physical material parameters. [ABSTRACT FROM AUTHOR]

For better design of filter rods with breakable capsules, filter rods with breakable capsules of different diameters and different positions were prepared and assembled into cigarette samples. The effects of filter rod design parameters on the major physical indexes, routine mainstream smoke indexes and nicotine filtration efficiency were investigated. The results showed that : 1) With the increase of capsule diameter, the filter ventilation rate and draw resistance of cigarettes increased by 28.4% and 28.1% respectively; the releases of tar and nicotine decreased by 6.8% and 3.3% respectively; and the nicotine filtration efficiency raised by 15.8% . 2) With the increase of the capsule distance to mouth end, ventilation rate and nicotine filtration efficiency were the lowest at the shortest distance between the capsule position and ventilation hole position. 3) Post capsule crushing, cigarette draw resistance significantly decreased by 210 Pa, the maximum increases of tar and nicotine releases reached 1.9 and 0.08 mg/cigarette respectively, and nicotine filtration efficiency decreased by 16.3%. 4) Post capsule crushing, filter ventilation rate and total ventilation rate reduced generally, cigarette draw resistance increased, and nicotine and tar releases raised gradually with the increase of capsule diameter. 5) Post capsule crushing, nicotine and tar releases increased gradually and nicotine filtration efficiency decreased gradually with the increase of the distance between the capsule position and mouth end. The maximum nicotine and tar releases and the minimum nicotine filtration efficiency appeared at the shortest distance between the capsule position and ventilation hole position. [ABSTRACT FROM AUTHOR]

In order to analyze the chemical components in the essential oil of cigar tobacco and to evaluate their effects, the essential oil of cigar tobacco was prepared by using subcritical extraction and molecular distillation technology. The enrichment effects of various components in the essential oil at different distillation temperatures were clarified. The main chemical components of the essential oil were analyzed by GC/MS, and the influences of mass fractions of various components in the essential oil on the sensory quality of cigarettes were further verified through sensory panel evaluation. The relationships between some aroma components and sensory evaluation indexes were studied via relevant analysis. The results showed that: 1) At the distillation temperature of 60-80 °C, the mass fractions of nicotine, alkanes and long-chain aliphatic esters were reduced, and the aroma components with cigar styles were effectively enriched. 2) The mass fractions of geranyl acetone, β-ionone, megastigmatrienone, dihydroactinidiolide, farnesyl acetone, phenylacetic acid, acetic acid, propionic acid, dihydro-β-ionone, n-hexanoic acid, 6-methyl-5-heptene-2-one, thujopsene and (E)-nerolidol in the essential oil significantly positively or extremely significantly positively correlated with the quality evaluation indexes of cigarettes, including aroma, comprehensive taste, woody and honeysweet scents. Therefore, these compounds could be used as the main indexes for evaluating the quality of essential oil of cigar tobacco. [ABSTRACT FROM AUTHOR]

To develop functional materials that can reduce phenol release in cigarette smoke, 36 natural deep eutectic solvents (NADESs) were designed and prepared based on the characteristics that phenolic hydroxyl groups could easily form hydrogen bonds. The structures and thermal stability of the synthesized products were characterized by Fourier transform infrared spectroscopy (FT-IR), elemental analysis (EA) and thermogravimetric analysis ( TG) . The performances of the synthesized products in reducing phenol release in cigarette smoke were evaluated by a simulating device for screening the harm-reducing abilities of these filter additives in mainstream cigarette smoke. The results showed that: 1) The FT-IR and EA results suggested that the NADESs were successfully synthesized. TG analysis indicated that the NADESs had good thermal stability up to 150 °C 2) Thirteen NADESs reduced phenol release in mainstream cigarette smoke by more than 30%. Among them, choline chloride-levulinic acid (ChCl-LA), betaine-levulinic acid (Bet-LA), choline chloride-DL-lactic acid (ChCl-Lac), L-proline-DL-lactic acid (Pro-Lac) and choline chloride-fructose (ChCl-Fru) reduced phenol release by more than 40%. In summary, NADESs could effectively reduce phenol release in cigarette smoke and they could be prepared with a simple, green and low cost process. [ABSTRACT FROM AUTHOR]

The research and application status of flavoring and moisturizing filter rods based on addition of additional materials (fragrance line, capsules, gel and particles) and raw materials (triacetin, wrap paper and acetate tow), and other flavoring and moisturizing filter rods were reviewed. It was pointed out that the flavoring and moisturizing filter rods based on addition of additional materials had more loading capacity and better controllability, but the principle of flavoring and moisturizing as well as the overall impact on cigarette quality were still lack of systematic research. The preparation process of the flavoring and moisturizing filter rods based on addition of raw materials was simple and the cost was low, but the loading capacity of the additive was small and it was easy to volatilize. So it was suitable to be an auxiliary means of flavoring and moisturizing. By optimizing the structure of the filter rod and adding the auxiliary agent to the other carriers, the other flavoring and moisturizing filter rods had more function of the filter rod and better controllability. However the structure was complex, the production cost was high and the quality control was difficult. These flavoring and moisturizing filter rods had some problems, such as imperfect production technology, unstable product quality control and high production cost. The future research can integrate the existing technical means and adopt the multi-element filter rod structure to effectively improve the fragrance and moisture retention performance of the filter rod. At the same time, it can also optimize the production process of filter rod to reduce the production cost and improve the quality stability of filter rod. [ABSTRACT FROM AUTHOR]

The single-factor experiment was used to investigate the effect of filter wrap' s air permeability, tipping paper's air permeability, and perforation row number on the filter ventilation rate of the cigarette. Furthermore, the effects of three factors and their interaction on the filter ventilation rate of the cigarette and the chemical composition of mainstream smoke by split-plot experiment were analyzed. The results showed that the filter ventilation rate of the cigarette increased with the increase of tipping paper's air permeability or perforation row number in single-factor experiment and split-plot experiment. In the range of 3300 ~ 8000 CU, the effect of the permeability of the formed paper on the ventilation rate of the cigarette filter was significant. After exceeding 8000 CU, the effect of filter wrap's air permeability on the filter ventilation rate of the cigarette decreased. The three factors of filter wrap's air permeability, tipping paper's air permeability, and perforation row number had significant interactions, which could coordinately adjust the filter ventilation rate of cigarette. With the increase of the filter wrap's air permeability, tipping paper's air permeability, and perforation row number, the content of nicotine, tar and COin the mainstream smoke of cigarette decreased. According to actual needs, the filter wrap's air permeability was 8000 CU, tipping paper's air permeability was 250 CU, and perforation row number was 3, which could reduce the content of nicotine, tar and CO in the cigarette smoke, and reduce the loss of smoke aroma. [ABSTRACT FROM AUTHOR]

In order to further improve the sensory quality of cigarettes, the essence was extracted from the natural tangerine, and dripped as tangerine flavored breakable capsule with different quality fractions. Test cigarettes were rolled with filters containing tangerine flavored breakable capsule. The physicochemical index and sensory quality of test cigarettes were evaluated. The results showed that: 1) Under the existing breakable capsule processing technology, stable and uniform breakable capsule could be prepared with the natural tangerine essence. 2) Compared with the control samples, the pressure drop of filter rods with capsules, the weight, draw resistance and ventilation rate of the cigarette samples increased. The release of tar and CO from the cigarette samples with breakable capsule decreased while the release of nicotine had no significant difference; After breakable capsule was crushed, the release of tar and CO increased to a certain extent, and the release of nicotine had no significant increase; 3 ) By adding breakable capsule, the stimulation of cigarettes was weakened, the aroma of the cigarettes was improved and enriched, meanwhile, the sensory quality and aspiration of interest of the cigarettes were enhanced significantly. [ABSTRACT FROM AUTHOR]

In order to study the influence of filter parameters on the release of 5 kinds of key roasted sweet aromas in mainstream smoke of fine cigarettes, 60 fine branches with different tow specifications, different filter plug pressure drops and diiferent filter ventilations were prepared, and the release of 5 kinds of key roasted sweet aromas in mainstream smoke was analyzed. The results showed that: 1) The diiference between the release of sterol and 5-methyl sterol in the mainstream smoke of fine cigarettes in diiferent tow specifications reached a very significant or significant level, and the diiference among the release of 3-methyl-2-cyclopenten-1-one, strawberry furanone, maltol and the total release of these 5 kinds of key roasted sweet aromas in diifer ent tow specifications were not significant. The comparison results showed that fine cigarettes with 11. 0Y/15000 tow had higher sterol and 5-methyl sterol release; 2) As the pressure drop of the filter rod rose, the total release of the 5 kinds of key roasted sweet aromas in mainstream smoke showed a decreasing trend; 3 ) With the increase of filter ventilation, the total release of 5 kinds of key roasted sweet aromas in mainstream smoke increased first and then decreased. [ABSTRACT FROM AUTHOR]

The classification and hazard of HAAs, the detection of heterocyclic aromatic amines (HAAs) in cigarette smoke, the metabolism research progress of main HAAs and monitoring methods of human exposure were reviewed. It was pointed out that HAAs were highly carcinogenic and mutagenic. There are ten main HAAs in cigarette smoke, and the higher contents are Harman, Norharman, AαC and MeAαC. Studies of major heterocyclic amines in cigarette smoke are mostly focused on AαC and MeAαC. The metabolic pathways of AαC and MeAαC have been clarified, but there is a slight difference in the literature regarding the amount of their metabolites. The exposure monitoring of HAAs is mainly achieved through the detection of prototype HAAs in human urine or hair, metabolites of HAAs can be used as exposure markers for monitoring the exposure of HAAs. Future research will focus on the synergistic mutagenesis of Harman and Norharman, metabolites of AαC and MeAαC as exposure markers, rapid and effective detection method to determine HAAs in biological sample and the correlation between smoking and the exposure of HAAs to further reduce the harmful-ness of HAAs and provide references for the study of "smoking and health". [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this study of Google and Baidu in mainland China is to identify the key contingencies to firm strategic responses to technical and institutional pressures. From an institutional logic perspective and Hirschman's model of exit, voice, and loyalty, this research proposes a few propositions which are intended to explain why foreign and local companies adopt different responses to similar institutional requirements or under similar institutional pressures. Design/methodology/approach – This study applies a historical chronological method by the recognition of certain types of events and key strategic activities conducted by two sample organizations from their foundations in mainland China till March 2010 when Google exited from China's internet search market. These activities were identified as the measurement of firm strategic responses to institutional pressures. Data were gathered from various sources, including documents published by sample organizations, online and media reports, etc. Findings – It is found that firms adopted similar responses to technical pressures which were determined by characteristics of the internet industry. However, their responses to institutional pressures, which were driven by the state logic for control of the internet, were dramatically different. As a multinational corporation, Google was faced with inherent tensions between home and host institutional requirements. When the state control pressures increased, Google eventually selected a voice and exit strategy. Baidu, as a local leading player in China's internet market, adopted a loyalty strategy through closer collaboration with local institutional constituents, including government agencies and clients, in addition to its investment in creating corporate images and reputation among local internet users. Originality/value – This research explores the dynamic and diverse responses of foreign and local companies to institutional pressures and advances our understanding of political properties in firm strategies and the importance of firm nationality in strategy making. [ABSTRACT FROM AUTHOR]

Background: We explored the impact of glycemic variability on the occurrence of periprocedural myocardial infarction and major adverse cardiovascular events (MACE) after coronary intervention in patients with stable angina pectoris (SAP) at 6months follow-up., Methods: From May 2015 to April 2016, a total of 746 patients with SAP were divided to high glycemic variability group (H group) (n=261) and low glycemic variability group (L group) (n=485). The primary end point was incidence of periprocedural myocardial infarction and MACE at 6months follow-up., Results: The occurrence of periprocedural myocardial infarction occurred in 18.8% of patients in H group and in 12.4% in L group (P=0.03). The incidence of MACE at 6months follow-up was 9.6% in H group and 4.5% in L group (P=0.01). Multivariable analysis suggested that high glycemic variability conferred a 53% risk increment of 6months follow-up MACE (odds ratio 2.13, 95% confidence interval 1.85-5.38; P=0.01)., Conclusions: The trial shows that higher blood glucose variability was correlated with higher incidence of periprocedural myocardial infarction and MACE at 6months follow-up., (Copyright © 2017. Published by Elsevier B.V.)