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Calcination of MgCO3is an important industrial reaction, but it causes significant and unfavorable CO2production. Calcination in a reducing green hydrogen atmosphere can substantially reduce CO2release and produce high value-added products such as CO or hydrocarbons, but the mechanism is still unclear. Here, the in situ transformation process of MgCO3interacting with hydrogen and the specific formation mechanism of the high value-added products are thoroughly investigated based on reaction thermodynamic, ab initio molecular dynamics (AIMD) simulations, and density functional theory (DFT) calculations. The reaction thermodynamic parameters of MgCO3coupled with hydrogen to produce CO or methane are calculated, revealing that increasing and decreasing the thermal reductive decomposition temperature favors the production of CO and methane, respectively. Kinetically, the energy barriers of each possible production pathway for the dominant products CO and methane are further calculated in conjunction with the AIMD simulation results of the transformation process. The results suggest that CO is produced via the MgO catalytic-carboxyl pathway (CO2*→ COOH*trans→ COOH*cis→ CO*→ CO), which is autocatalyzed by MgO derived from the thermal reductive decomposition of MgCO3. For the mechanism of methane formation, it prefers to be produced by the stepwise interaction of carbonates in the MgCO3laminates with hydrogen adsorbed on their surfaces (direct conversion pathway: sur-O–CO → sur-O-HCO → sur-O-HCOH → sur-O-HC → sur-O–CH2→ sur-O–CH3→ sur-O + CH4*).

In situ thermal desorption (ISTD) provides an efficient solution to remediation of soil and groundwater contaminated with nonaqueous phase liquids (NAPLs). Establishing a relationship between the subsurface temperature rise and NAPL removal is significant to reduce energy consumption of ISTD. However, the co-boiling phenomenon between NAPL and water poses a great challenge in developing this relationship due to the nonequilibrium heat and mass transport effects. We performed a systematic experimental investigation into the local temperature rise patterns at different distances from a NAPL pool and under different degrees of superheat by selecting four representative NAPLs (i.e., trichloroethylene, tetrachlorethylene, n-hexane, and n-octane) according to their density and boiling point relative to water. The patterns of temperature rise indicated that the underground temperature field can be divided into three zones: the zone of local thermal equilibrium, the nonequilibrium zone affected by co-boiling, and the zone unaffected by co-boiling. We developed a pattern-recognition-based approach, which considers the effects of local heat and mass transport to establish a qualitative correlation between the temperature rise and NAPL removal. Our results give deeper insights into the understanding of subsurface temperatures in ISTD practice, which can serve as the guideline for more accurate and sustainable remediation.

The first base-mediated intermolecular cyclization of arylaldehydes and terminal arylacetylenes for the synthesis of a wide range of pyrroles in a single step has been described. The developed methodology used commercially available starting materials and tolerated a broad range of functional groups affording 2,3,5-triaryl-substituted-1H-pyrroles with good yields (up to 92% yield) under mild conditions. The possible mechanism was also discussed.

Deep learning is usually combined with a single detection technique in the field of disease diagnosis. This study focused on simultaneously combining deep learning with multiple detection technologies, fluorescence imaging and Raman spectroscopy, for breast cancer diagnosis. A number of fluorescence images and Raman spectra were collected from breast tissue sections of 14 patients. Pseudo-color enhancement algorithm and a convolutional neural network were applied to the fluorescence image processing, so that the discriminant accuracy of test sets, 88.61%, was obtained. Two different BP-neural networks were applied to the Raman spectra that mainly comprised collagen and lipid, so that the discriminant accuracy of 95.33% and 98.67% of test sets were gotten, respectively. Then the discriminant results of fluorescence images and Raman spectra were counted and arranged into a characteristic variable matrix to predict the breast tissue samples with partial least squares (PLS) algorithm. As a result, the predictions of all samples are correct, with minor error of predictive value. This study proves that deep learning algorithms can be applied into multiple diagnostic optics/spectroscopy techniques simultaneously to improve the accuracy in disease diagnosis.

The density jump at the inner core boundary of the Earth is poorly constrained by seismic data. One sensitive measure of the jump is the eigenperiod of the inner core wobble (ICW). Although theoretical studies on the ICW have been ongoing for decades, no observed ICW signal has been reported. To increase the detection level, here we use a recently proposed AR‐z method to analyze the 1960–2017 polar motion time series. We finally identify a +8.7 ± 0.2 year prograde motion with an ~2.67 ± 0.04 milliarcsecond amplitude. After confirming that this signal is almost a stationary oscillation and that atmospheric/oceanic/hydrological effects cannot seem to excite this signal, we carefully suggest that this ~8.7 year signal is possibly the ICW. According to this suggestion, we reconstruct a new 1‐D density model with a 507 ± 15 kg/m3inner core boundary density jump. This new model can also provide a better fit than Preliminary Reference Earth model to the seismic overtone 2S1. The eigenperiod of the ICW is directly related to the density jump at the inner core boundary (ICB) (which is still poorly known). Although theoretical studies on the ICW have been ongoing for decades, only Guo et al. (2005) have tried unsuccessfully to detect the ICW in the PM time series. In this study, we use the AR‐z spectrum, which has significantly higher sensitivity and frequency resolution than the Fourier (and maximum‐entropy) spectrum, especially when the signal‐to‐noise ratio is low. We identify a +8.7 ± 0.2 year prograde motion from the PM as the possible ICW. Our results provide useful constraints on the density jump at the ICB and can further strengthen the understanding of Earth's deep structure and dynamics. The AR‐z spectrum method is used to search for the inner core wobble (ICW) in the polar motionA +8.7 ± 0.2 year prograde motion, with an ~2.67 ± 0.04 mas amplitude, is suggested as the possible ICWA modified core density profile is estimated by the suggested ICW period

Three side-chain liquid crystalline ionomers (SLCIs) with sulfonic group (SLCI-S), quaternary ammonium salt group (SLCI-N), and carboxylic group (SLCI-C) were synthesized by graft copolymerization upon polymethylhydrosiloxane, respectively. The SLCIs were used to blend with poly (butylene terephthalate) (PBT) and polypropylene (PP). The morphological structure and mechanical properties of the blends were investigated by scanning electron microscopy (SEM). SEM results indicated that the addition of SLCIs lead to finer and better dispersion of PP polymer in the blends relative to the blends with no SLCIs added. The compatibilization of SLCIs in the blends were in the increasing order of SLCI-S> SLCI-N> SLCI-C, which was due to the specify interaction between SLCIs and PBT increased with the increasing order of SLCI-S>SLCI-N>SLCI-C. The mechanical properties were improved when the proper amount of SLCI was added, which enabled improve adhesion at the interface. The mechanical property of PBT/PP/SLCI-S was higher than that of PBT/PP/SLCI-N, which was higher than that of PBT/PP/SLCI-C.

A model of combining of guard rings and buried n+ layer in mitigating charge collection and charge sharing is presented in this paper. 3-D TCAD simulation results indicate that for 90-nm CMOS process, PMOS charge collection and charge sharing can be mitigated more effectively with the combination model than the solely use of guard rings or buried n+ layer. With the combination, a noticeable improvement on angled ion strikes is also represented. The model shows a significant advantage in high-energy ion strikes and angled ion strikes.

In this paper, design of a LDPC decoder in CMMB is presented. LDPC decoding algorithms for CMMB are analyzed and the optimal decoding algorithm-Normalized MSA are used to implement the decoder, and the algorithm is simulated to determine the design parameters. A partial parallel architecture based on Normalized MSA algorithm is proposed, and the architecture is simulated with a fixed-point model to determine the best quantification scheme for initial information and intermediate data format.

This paper based on the Whole Life Appraisal, Value Engineering and Environmental Economics theories, referred the Green Building Evaluation Criterion and Administration Method of Commercial Residential Building Function Appraisal, then built the green building economical appraisal system and integrate appraisal model which based on the fuzzy mathematic principal, expanded the thinking of green building economical appraisal methods.

As one of the largest families of angiosperms, the Orchidaceae family is diverse. Dendrobiumrepresents the second largest genus of the Orchidaceae. However, an assembled high-quality genome of species in this genus is lacking. Here, we report a chromosome-scale reference genome of Dendrobium chrysotoxum, an important ornamental and medicinal orchid species. The assembled genome size of D. chrysotoxumwas 1.37 Gb, with a contig N50 value of 1.54 Mb. Of the sequences, 95.75% were anchored to 19 pseudochromosomes. There were 30,044 genes predicted in the D. chrysotoxumgenome. Two whole-genome polyploidization events occurred in D. chrysotoxum. In terms of the second event, whole-genome duplication (WGD) was also found to have occurred in other Orchidaceae members, which diverged mainly via gene loss immediately after the WGD event occurred; the first duplication was found to have occurred in most monocots (tau event). We identified sugar transporter (SWEET) gene family expansion, which might be related to the abundant medicinal compounds and fleshy stems of D. chrysotoxum. MADS-box genes were identified in D. chrysotoxum, as well as members of TPS and Hsp90 gene families, which are associated with resistance, which may contribute to the adaptive evolution of orchids. We also investigated the interplay among carotenoid, ABA, and ethylene biosynthesis in D. chrysotoxumto elucidate the regulatory mechanisms of the short flowering period of orchids with yellow flowers. The reference D. chrysotoxumgenome will provide important insights for further research on medicinal active ingredients and breeding and enhances the understanding of orchid evolution.

The marvelously diverse Orchidaceae constitutes the largest family of angiosperms. The genus Cymbidiumin Orchidaceae is well known for its unique vegetation, floral morphology, and flower scent traits. Here, a chromosome-scale assembly of the genome of Cymbidium ensifolium(Jianlan) is presented. Comparative genomic analysis showed that C. ensifoliumhas experienced two whole-genome duplication (WGD) events, the most recent of which was shared by all orchids, while the older event was the τ event shared by most monocots. The results of MADS-box genes analysis provided support for establishing a unique gene model of orchid flower development regulation, and flower shape mutations in C. ensifoliumwere shown to be associated with the abnormal expression of MADS-box genes. The most abundant floral scent components identified included methyl jasmonate, acacia alcohol and linalool, and the genes involved in the floral scent component network of C. ensifoliumwere determined. Furthermore, the decreased expression of photosynthesis-antennae and photosynthesis metabolic pathway genes in leaves was shown to result in colorful striped leaves, while the increased expression of MADS-box genes in leaves led to perianth-like leaves. Our results provide fundamental insights into orchid evolution and diversification.