Some functional proteins undergo conformational changesto exposehidden binding sites when a binding molecule approaches their surface.Such binding sites are called cryptic sites and are important targetsfor drug discovery. However, it is still difficult to correctly predictcryptic sites. Therefore, we introduce an advanced method, CrypToth,for the precise identification of cryptic sites utilizing the topologicaldata analysis such as persistent homology method. This method integratestopological data analysis and mixed-solvent molecular dynamics (MSMD)simulations. To identify hotspots corresponding to cryptic sites,we conducted MSMD simulations using six probes with different chemicalproperties: dimethyl ether, benzene, phenol, methyl imidazole, acetonitrile,and ethylene glycol. Subsequently, we applied our topological dataanalysis method to rank hotspots based on the possibility of harboringcryptic sites. Evaluation of CrypToth using nine target proteins containingwell-defined cryptic sites revealed its superior performance comparedwith recent machine-learning methods. As a result, in seven of ninecases, hotspots associated with cryptic sites were ranked the highest.CrypToth can explore hotspots on the protein surface favorable toligand binding using MSMD simulations with six different probes andthen identify hotspots corresponding to cryptic sites by assessingthe protein’s conformational variability using the topologicaldata analysis. This synergistic approach facilitates the predictionof cryptic sites with a high accuracy.

Purification of industrial toluene from technical to reagent grade using Diahope activated carbon in a pilot-scale fixed-bed column

Introduction: Xylene (XL) is the most commonly used clearing agent in Papanicolaou staining. XL is hazardous and toxic chemical and prolonged exposure to XL can cause many ill-health effects. The health risk due to XL can be minimized by substituting XL with less hazardous clearing reagents such as Pine Oil (PO), Eucalyptus oil (EO), or Limonene (LM). The objective of this study was to compare the clearing ability, staining quality, preservation of morphology, physical properties, and cost of XL, PO, EO, and LM. Methods: Four smears were prepared from each of 50 serous effusions and were subjected to Papanicolaou stain. Out of four smears, one each was exposed to clearing specifically with XL (control), PO (test), EO (test), and LM (test). Test smears were compared with control for clearing, staining and morphology; graded as excellent, good or fair and further scored as 3, 2, 1, and the quality index (QI) was calculated. Statistical analysis was performed and the p value was calculated. In addition, the physical properties and cost of all the reagents were compared. Results: QI was 0.96 for both XL and PO, whereas 0.92 and 0.54 for EO and LM, respectively. Compared to XL, the quality of staining, clearing and morphology of PO and EO were statistically not significant, whereas the difference was statistically significant with LM (p = 0.005). Physical properties such as volatility, flammability, miscibility with alcohol and DPX and the refractive indices of all the reagents were almost similar and all were recyclable. Odor was pungent for XL and EO but was pleasant for PO and LM. The cost was less for PO as compared to others. Conclusion: PO was a natural, less hazardous, less toxic, and economical clearing agent and can be considered as a substitute for XL.

The determination of the solubility, enthalpy, and entropy of solutions of methyl Furan-2,5-Dimethylenedicarbamate and its hydrides in different solvents

Abstract Au nanoclusters with tailored photoluminescence can be obtained through controlled nanoparticle ligand interface chemistry. The present work reports molecular gold nanoclusters with tuneable photoluminescence emission from 600 to 700 nm using N,N′,N″‐trialkyl (11‐mercaptoundecyl)ammonium chloride ligands as capping‐agents. The tunability within red spectral region is regulated through specific interface chemistry between gold nanoclusters of molecular range and functional groups of the quaternary ammonium head over N,N′,N″‐trialkyl(11‐mercaptoundecyl)ammonium chloride. Combined understanding obtained from the spectroscopy, microscopy, and density functional theory studies demonstrate that the functional group specific electronic interactions at the interfaces steer the emission characteristics of “molecular” Au nanoparticles. The study clearly identifies that bulkier functional groups, i.e., triethyl, tripropyl, tributyl, and dimethyl benzene over N+ (of thiol ligand) through their steric effects minimize the particle size giving rise to tunable photoluminescence emission in red spectral region. However, the red shift seen in the emission Au nanoclusters with N‐(11‐mercaptoundecyl)‐N,N′‐dimethylbenzenammonium chloride ligand in contradiction to particle size effect is computationally proved to be due to the delocalization of electron density from benzene aromatic ring to N+ of ammonium head leading to a reduction in the HOMO‐LUMO energy gap.

Abstract The concept of a domino‐type reaction has been applied in a wide range of fields such as synthetic organic chemistry, material engineering, and life science. To extend the domino concept to redox chemistry, we designed and synthesized a dimeric quinodimethane (QD) with a nonplanar dithiin spacer. The domino‐redox properties can be activated by raising the temperature, based on a thermally equilibrated twisted conformation of QD, which has a higher HOMO level that is more readily oxidized. After one QD unit is oxidized (trigger), steric repulsion and electronic interaction between electrophores make the neighboring QD unit adopt a twisted conformation (domino process), which facilitates the following oxidation. Thus, a domino‐redox reaction was achieved for the first time by a change in the HOMO level due to a drastic change in the molecular conformation.

The concept of a domino-type reaction has been applied in a wide range of fields such as synthetic organic chemistry, material engineering, and life science. To extend the domino concept to redox chemistry, we designed and synthesized a dimeric quinodimethane (QD) with a nonplanar dithiin spacer. The domino-redox properties can be activated by raising the temperature, based on a thermally equilibrated twisted conformation of QD, which has a higher HOMO level that is more readily oxidized. After one QD unit is oxidized (trigger), steric repulsion and electronic interaction between electrophores make the neighboring QD unit adopt a twisted conformation (domino process), which facilitates the following oxidation. Thus, a domino-redox reaction was achieved for the first time by a change in the HOMO level due to a drastic change in the molecular conformation.

The whole complex of air protection activities has been planned in the RF with its aim to reduce levels of ambient air pollution. It is being implemented actively now and as a result the quality of the environment should improve for more than 7 million people. In this study, an algorithm has been suggested for assessing effectiveness of air protection activities. It includes six subsequent stages. The algorithm was tested at heat and power enterprises located in a region participating in the Clean Air Federal project. As a result, it was established that these enterprises were sources of potential public health risks; 70 % of them belonged to high risk categories. Until air protection activities are implemented, heat and power enterprises pollute ambient air in some areas in the city (up to 29.9 single maximum MPC; up to 6.9 average daily MPC; up to 19.0 average annual MPC), create unacceptable health risks (up to 25.8 HI for acute exposure, 22.7 HI for chronic exposure, CRT is up to 3.28∙10-4), and cause more than 87 thousand additional disease cases. Implementation of air protection activities at heat and power enterprises will reduce local levels of ambient air pollution but we still expect hygienic standards to be violated for 10 chemicals up to 3–22 MPC and high health risks are likely to persist (up to 6.5–25.5 HI for acute exposure, 11.9–22.4 HI for chronic exposure, CRT will be up to 3.28∙10-4). Effectiveness of the air protection activities planned at heat and power enterprises corresponds to the target levels of the gross pollutant emissions (reduction by 20.56 % by 2024) set within the Clean Air Federal project but it is estimated as ‘unacceptable’ as per the health harm indicator, which is additional disease cases associated with activities of these enterprises (< 20 %). It is necessary to implement additional air protection activities with respect to 12 pollutants (nitrogen dioxide, particulate matter, carbon (soot), carbon oxide, sulfur dioxide, dihydrosulfide, inorganic dust containing silicon dioxide in %: 70–20, dimethyl benzene, ethyl benzene, benzene, formaldehyde, and kerosene); to use the best available technologies with respect to the most hazardous chemicals; to monitor public health in areas with elevated health risks; to implement complex medical and preventive activities.

The whole complex of air protection activities has been planned in the RF with its aim to reduce levels of ambient air pollution. It is being implemented actively now and as a result the quality of the environment should improve for more than 7 million people. In this study, an algorithm has been suggested for assessing effectiveness of air protection activities. It includes six subsequent stages. The algorithm was tested at heat and power enterprises located in a region participating in the Clean Air Federal project. As a result, it was established that these enterprises were sources of potential public health risks; 70 % of them belonged to high risk categories. Until air protection activities are implemented, heat and power enterprises pollute ambient air in some areas in the city (up to 29.9 single maximum MPC; up to 6.9 average daily MPC; up to 19.0 average annual MPC), create unacceptable health risks (up to 25.8 HI for acute exposure, 22.7 HI for chronic exposure, CRT is up to 3.28∙10-4), and cause more than 87 thousand additional disease cases. Implementation of air protection activities at heat and power enterprises will reduce local levels of ambient air pollution but we still expect hygienic standards to be violated for 10 chemicals up to 3–22 MPC and high health risks are likely to persist (up to 6.5–25.5 HI for acute exposure, 11.9–22.4 HI for chronic exposure, CRT will be up to 3.28∙10-4). Effectiveness of the air protection activities planned at heat and power enterprises corresponds to the target levels of the gross pollutant emissions (reduction by 20.56 % by 2024) set within the Clean Air Federal project but it is estimated as ‘unacceptable’ as per the health harm indicator, which is additional disease cases associated with activities of these enterprises (< 20 %). It is necessary to implement additional air protection activities with respect to 12 pollutants (nitrogen dioxide, particulate matter, carbon (soot), carbon oxide, sulfur dioxide, dihydrosulfide, inorganic dust containing silicon dioxide in %: 70–20, dimethyl benzene, ethyl benzene, benzene, formaldehyde, and kerosene); to use the best available technologies with respect to the most hazardous chemicals; to monitor public health in areas with elevated health risks; to implement complex medical and preventive activities.

Multicolor fluorescent probes for volatile organic vapors based on poly(tetraphenylethylene-co-phenylene)s prepared via solid-state oxidative coupling polymerization

ABSTRACT: The widely-used plastics, especially low-density polyethylene (LDPE), have resulted in a considerable accumulation of plastics in the waste stream, causing a global environmental problem. Therefore, the research aims to examine the thermal and catalytic degradation of waste LDPE plastic using spent fluid catalytic cracking (FCC) catalyst and compare the properties of the produced liquid oils with commercial fuels. The potential of converting the most energy from waste plastics to valuable liquid oil, gaseous, and char was investigated. A batch reactor was used to thermally and catalytically degrade LDPE at temperatures 350 to 550oC and catalyst to plastic ratio of 0.10 to 0.25. The physical properties of the produced liquid oils, flash point, pour point, viscosity, API-gravity, carbon residue, density, etc., were determined using standard methods. We characterized the chemical properties of produced pyrolysis liquid oils with Gas chromatography-mass spectrometry (GC-MS). The liquid oil, gas, and char produced at catalyst to plastic ratio of 0.20 at 500oC were 92.7 wt.%, 6.1 wt.%, and 1.2 wt.% respectively. The thermal pyrolysis at 500 oC gave 76.6 wt.%, 20.7 wt.%, and 2.7 wt.% for produced liquid oil, gas, and char, respectively. The GC-MS shows that the produced LDPE liquid oil contains many hydrocarbons from C7-C29. The major hydrocarbons common to LDPE are benzene, 1, 3 dimethyl benzene, and toluene. The produced liquid oil’s properties compare favorably with that of commercial fuels.

Gasoline obtained from the fractionation of indigenous natural gas condensate has low octane number (78) and is therefore of limited uses. Lead-based octane boosting and catalytic reforming are not the viable methods for many fractionation plants. This study was therefore aimed to develop an inexpensive conceptual alternative method for boosting the octane number of gasoline. Natural gas concentrated in methane having high octane number (more than 100) was absorbed in the gasoline to boost the octane number partially (86). Selective additives i.e. ethanol, tert-butyl alcohol, methylcyclopentane, toluene, iso-octane and xylene were blended first with the gasoline to aid the absorption of natural gas molecules. The loss of absorbed gas molecules from gasoline with the increase in temperature was also observed. It is therefore required to try for avoiding any increase in temperature in the finished gasoline. The developed conceptual method is promising. The findings of this simulation study would be useful for more studies towards the development of an affordable alternative method for fractionation plants for boosting the octane number of gasoline derived from natural gas condensate.

The aim of this paper was to observe the anti-inflammatory action and mechanism of Lonicerae Japonicae Flos extract and Lonicerae Flos extract in xylene-induced ear swelling experiment and lipopolysaccharide(LPS)-induced RAW264.7 cell inflammatory model. In vivo, xylene-induced mouse auricle swelling model was used to detect the auricle swelling degree and swelling inhibition rate of Lonicerae Japonicae Flos extract and Lonicerae Flos extract; the pathological changes of mice auricle were observed by hematoxylin eosin(HE) staining. In vitro, RAW264.7 inflammatory cell model was induced by LPS, where the cytotoxic effects of Lonicerae Japonicae Flos extract and Lonicerae Flos extract on RAW264.7 cells were detected by CCK-8 method; Griess method was used to detect the effect of Lonicerae Japonicae Flos extract and Lonicerae Flos extract on nitric oxide(NO) production, and ELISA method was used to detect the content of inflammatory factors interleukin-6(IL-6), IL-1β, and tumor necrosis factor-α(TNF-α). At last, Western blot was used to detect the protein changes of cyclooxygenase 1(COX1), COX2 and inducible nitric oxide synthetase(iNOS) for RAW264.7 cells. The results showed that both Lonicerae Japonicae Flos extract and Lonicerae Flos extract could significantly inhibit the degree of auricle swelling caused by xylene in mice and the inhibition rate was positively correlated with the drug dose. Furthermore, both of them could reduce the infiltration of lymphocytes and neutrophils in mouse ear tissues. For in vitro experiments, both Lonicerae Japonicae Flos extract and Lonicerae Flos extract inhibited NO secretion in RAW264.7 cells, down-regulated the release of IL-1β, IL-6 and TNF-α, and down-regulated iNOS protein and COX2, NF-κB p65 protein content. In conclusion, both Lonicerae Japonicae Flos extract and Lonicerae Flos extract have good anti-inflammatory effect, and the mechanism may be related with the inhibition of NF-κB signaling pathway.

Influence of 3D morphology on the performance of all-polymer solar cells processed using environmentally benign nonhalogenated solvents

The catalytic activity, selectivity to xylenes and time-on-stream stability were investigated in the transalkylation of toluene with 1, 2, 4-trimethylbenzene. The catalytic tests were carried out in a fixed bed reactor over zeolite Beta (Si/Al = 12.5, 75 and 150) and Y (Si/Al = 2.6, 6, 15 and 30). The operating parameters used were 400 °C, 1.0 Mpa, H2/HC = 4 and WHSV of 5 h-1. The length of each catalytic testing experiment was 50 hours, and for zeolite beta samples, the highest stability and selectivity to xylenes were achieved using the lowest Si/Al ratio with conversion of 41 wt. % and selectivity of 61 wt. %. In contrast, zeolites Y with Si/Al ratio of 2.6 showed the highest deactivation rate, whereas Y zeolites with Si/Al = 6 – 30 exhibited similar conversion (~ 27 wt. %) and selectivity to xylenes (~ 43 wt. %). The effects of Bronsted and Lewis acid sites on catalytic results are discussed.

Spectroscopic investigation and non linear optical activity study on 7,7,8,8-tetra cyano quino dimethane

Tin diacetate and aluminium isopropoxide in equimolar proportion in xylene affords the complex [(OAc)SnOAl(OPr i ) 2 ] which on reaction with Ti(OPr n ) 4 in 1:1 molar ratio yielded a new organoheterotrimetallic-μ-oxoisopropoxide-μ-oxon-propoxide [SnO 2 TiAl(OPr i ) 2 (OPr n ) 3 ] with continuous liberation of isopropyl acetate and propyl acetate formed during the course of reaction. The preparation of Schiff base complexes of the compound [SnO 2 TiAl(OPr i ) 2 (OPr n ) 3 ] was carried out in refluxing benzene by the reaction of µ-oxomixedpropoxide compound in different molar ratios (1:1 and 1:2) with Schiff bases (1-(2-Pyridyl) ethanonehydrazine carboxamide (HSB 1 ) and 1-Furanyl) ethanonehydrazin carboxamide (HSB 2 ). The complexes were characterized by spectral analysis (IR, 1 H, 13 C, 119 Sn, 27 Al NMR and mass spectra). The spectral studies confirmed that the proposed framework of the new organoheterotrimetallic complexes and indicated a tetrahedral geometry around the central metal atom.

A less toxic alternative to Xylene as a Demountant

The reactions of 1-tert butyl-5-thiotetrazole (HtttBu) with Na[BH4] provides Na[H2B(tttBu)2] (Na[1]) or Na[HB(tttBu)3] (Na[2]) in refluxing THF or xylene, respectively. Treating [RuCl(Ph)(CO)(PPh3)2] with Na[2] affords the triply-buttressed ruthenaboratrane [Ru(CO)(PPh3){κ4-B,S,S',S''-B(tttBu)3}] (5) whilst Na[1] with [IrCl(CO)(PPh3)2] or [RuCl(Ph)(CO)(PPh3)2] provides rare examples of doubly-buttressed metallaboratranes [IrH(CO)(PPh3){κ3-B,S,S'-BH(tttBu)2}] (7) and [Ru(CO)(PPh3)2{κ3-B,S,S'-BH(tttBu)2}] (12), the latter via the isolable thiotetrazoylborate complex [Ru(Ph)(CO)(PPh3){κ3-H,S,S'-H2B(tttBu)2}] (11).

Volatile organic compounds (VOCs) samples were collected and analyzed for the surface coating processes of aluminum products in Foshan. The concentration levels of VOCs from solvent-based coating (63.90-149.67 mg·m-3) are much higher than that from water-based, electrophoretic, and powder coating (2.99-21.93 mg·m-3). With respect to the VOC composition, aromatics are the main VOC group of solvent-based coating emission, ranging from 52.32%-71.55%. Typical species include toluene, ethylbenzene, xylene, and ethyl acetate. The VOCs emitted from water-based coating are mainly oxygenated VOCs, such as ethyl acetate (48.59%) and tetrahydrofuran (8.43%), while the percentage of aromatics (11.32%) is lower than that of solvent-based coating. Isopropanol is the most abundant species of electrophoretic coating emissions, accounting for up to 81.19% of the VOCs. The major VOC compounds of powder coating processes are acetone (30.25%), propane (15.48%), ethylene (12.15%), ethane (9.35%), and n-butane (5.16%). The calculation of the ozone formation potential (OFP) shows that the solvent-based coating has the highest OFP (3.89 g·g-1), followed by powder coating (2.53 g·g-1), while water-based and electrophoretic coating have lower OFPs (1.31 and 0.85 g·g-1, respectively). The most important contributor to OFP of solvent-based coating are aromatics, especially C7-C10 aromatics. The major contributors of water-based coating are ethyl acetate, m/p-xylenes, and toluene, with contributions of 23.24%, 21.76%, and 17.07%, respectively. The key reactive components of powder coating are ethylene, propene, and 1-butene; the sum of alkenes accounts for 71.11% of the OFP. With respect to the contribution of VOCs emitted from electrophoretic coating to the OFP, the percentage of isopropanol (65.08%) is significantly larger than that of other species (<6%).