[en] In recent years, among the problems of anthropogenic pollution of nature, the problem of exposure to organic substances of different classes has attracted great attention. Therefore, it is important to study the laws of the photochemical formation of oxygen-containing organic molecules, taking into account the anomalous phenomena occurring in the atmosphere. During the photooxidation of methane in the atmosphere, the most common hydrocarbon formaldehyde is formed. The average life span of formaldehyde in the atmosphere is approximately three hours. A study was made of the kinetic laws of formation of oxygen-containing (formaldehyde, formic acid and acetone) hydrocarbons during the photochemical conversion of air-methane mixtures.

[en] In this study, walnut processing by-product was served as filler to make three-layer plywood, and the physical-mechanical properties were also discussed. The results showed that the formaldehyde emission of plywood corresponding to walnut shell and walnut dregs decreased by 0.0542 mg/L and 0.066 mg/L, respectively. The properties of plywood filled with walnut dregs are better than that of walnut shell filler, and the formaldehyde emission of the corresponding plate is lower. At the same time, compared with flour, the wet bond strength of walnut shell plywood increased by 0.0332 MPa, and that of walnut dregs plywood decreased by 0.123 MPa, but they all met the national standards. (paper)

[en] This study investigated the effect of mixed material composition of jabon (Anthocephalus cadamba Miq.) and andong (Giganthochloa pseudoarundinaceae Steud.) particleboards on their resistance to subterranean termite (Coptotermes curvignatus Holmgren). Six types of 35cm × 35cm × 1.2 cm particleboards were produced and glued with phenol formaldehyde in the proportion of 100:0, 70:0, 60:40, 50:50, 40:60 and 30:70 for jabon and andong. Those panels were tested according to SNI 727-2014. The results showed that material composition of jabon and andong was significantly influenced weight loss and termite mortality. Particleboard with 30:70 jabon-andong proportions had the lowest weight loss (4.28%) and classified as resistant class. Termite mortality rate escalated as jabon composition in the panel decreased. (paper)

[en] Several interesting features in trajectory were observed in the direct dynamics study of formaldehyde dissociation above radical dissociation limit. The hydrogen atom deliberately placed on the radical dissociation path can turn around at some distance from C without completion of dissociation and return to HCO moiety, colliding with it just as in a radical-radical recombination and producing a highly energized molecule. Excursion of a hydrogen atom to a distance of 6-8 bohrs and migration of a hydrogen atom back and forth between C and O are two of the most interesting features exhibited by the energized molecule. A series of excursions is seen to lead to a different kind of dissociation resembling roaming-like dissociation characterized by high vibrational excitation of H₂ fragment. It is suggested that excursion occurs due to involvement of two different force field systems that exhibit discontinuity in 6-8 bohrs from HCO moiety. We argue that roaming is a non-zero impact parameter version of the excursion

[en] The reaction mechanism between cyclopropenylidene and formaldehyde has been systematically investigated employing the MP2/6-311+G* level of theory to better understand the cyclopropenylidene reactivity with carbonyl compound. Geometry optimization, vibrational analysis, and energy property for the involved stationary points on the potential energy surface have been calculated. Energies of all the species are further corrected by the CCSD(T)/6-311+G* single-point calculations. It was found that one important reaction intermediate (INTa) has been located firstly via a transition state (TSa). After that, the common intermediate (INTb) for the two pathways (1) and (2) has been formed via TSb. At last, two different products possessing three- and four-membered ring characters have been obtained through two possible reaction pathways. In the reaction pathway (1), a three-membered ring alkyne compound has been obtained. As for the reaction pathway (2), it is the formation of the four-membered ring conjugated diene compound. The energy barrier of the rate determining step of pathway (1) is lower than that of the pathway (2), and the ultima product of pathway (2) is more stable than that of the pathway (1)

No abstract available

[en] Highlights: • Comprehensive analysis of available rotation-vibration data • High-accuracy measurements of pure rotational transitions within 4 states • High accuracy line list presented. Published high-resolution rotation-vibration transitions of H${}_2^{12}$C${}^{16}$O, the principal isotopologue of methanal, are analyzed using the MARVEL (Measured Active Rotation-Vibration Energy Levels) procedure. The literature results are augmented by new, high-accuracy measurements of pure rotational transitions within the ground, ${\nu }_3,$ ${\nu }_4,$ and ${\nu }_6$ vibrational states. Of the 16 596 non-redundant transitions processed, which come from 43 sources including the present work, 16 403 could be validated, providing 5029 empirical energy levels of H${}_2^{12}$C${}^{16}$O with statistically well-defined uncertainties. All the empirical rotational-vibrational energy levels determined are used to improve the accuracy of ExoMol’s AYTY line list for hot formaldehyde. The complete list of collated experimental transitions, the empirical energy levels determined, as well as the extended and improved line list are provided as Supplementary Material.

[en] We report results of the H₂CO and H110α survey toward 281 UCHII regions using the Urumqi 25m radio telescope. We obtained 37 new H₂CO detections, and H110α was simultaneously detected in eight of them. Only H110α was detected in another UCHII region. We calculated kinematic distances of nine UCHII regions with the detected H110α and resolved the kinematic distance ambiguity for six of them. The detection rate of H₂CO of our observation was 13.2%, which is low compared with one of the other authors. The possible reason is that the sensitivity of our telescope is relatively low.

[en] The study for a number of 5-iododeoxyuridine analogues has been exclusively since the potential antiviral and antitumor therapeutic agents. The major goal of those studies was to prepare the more suitable radioiodine-labeled nucleoside analogues are effective and stable in vivo biodistribution as well as in vitro test. In this study, we wish to report here an efficient synthetic route for carbocyclic radiopharmaceuticals starting from cyclopentadiene

[en] Application of next-generation sequencing (NGS) technology to routine clinical practice has enabled characterization of personalized cancer genomes to identify patients likely to have a response to targeted therapy. The proper selection of tumor sample for downstream NGS based mutational analysis is critical to generate accurate results and to guide therapeutic intervention. However, multiple pre-analytic factors come into play in determining the success of NGS testing. In this review, we discuss pre-analytic requirements for AmpliSeq PCR-based sequencing using Ion Torrent Personal Genome Machine (PGM) (Life Technologies), a NGS sequencing platform that is often used by clinical laboratories for sequencing solid tumors because of its low input DNA requirement from formalin fixed and paraffin embedded tissue. The success of NGS mutational analysis is affected not only by the input DNA quantity but also by several other factors, including the specimen type, the DNA quality, and the tumor cellularity. Here, we review tissue requirements for solid tumor NGS based mutational analysis, including procedure types, tissue types, tumor volume and fraction, decalcification, and treatment effects