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Forest–grassland ecotone (FGE) has essential ecological and economic value. Unfortunately, it is impacted greatly by environmental changes and anthropogenic disturbance, and is considered one of the most severely threatened biomes in China. To protect Chinese FGE, identifying its exact boundary and exploring its landscape structure dynamic are badly needed, especially on nationwide scale at one‐year temporal resolution. Here, we mapped the annual FGE distribution of China from 1990 to 2020, investigated its changing trends of area, location and landscape patterns, and revealed the underlying driving factors. Our results showed that FGE area over the 31 years totaled 1 011 870 km2, covering about 10.54% of China's land. The FGE area first increased from 1990 and peaked in 1999, and then kept decreasing until 2020. The FGE gravity center has moved accumulatively 590.15 km over the 31 years, with the net moving distance of 228.76 km southwestward. From 1990 to 2020, forest area increased continuously while grassland and cropland area decreased, but these three landscape types had been dominating the FGE. The increase in forest area was largely converted from grassland. The decline in grassland mainly resulted from its conversion into cropland and forest. Meanwhile, the conversion of cropland to grassland supplemented grassland loss to a certain extent. At landscape level, the total area with decreased fragmentation is larger than that with increased fragmentation. Returning Farmland to Grassland Project and land reclamation were primary drivers for changes of fragmentation in the northern and middle part of the FGE, while temperature and precipitation were primary drivers in southern part. Our results will improve the understanding into the dynamic trends of distribution and pattern of FGE at nationwide scale, and thus help to optimize the designing of ecological projects and protective schemes for FGE as a unique and integral biome. [ABSTRACT FROM AUTHOR]

In this paper, we investigated the role of excited-state hydrogen bonding in the photocatalytic carbon dioxide reduction reaction (CO2RR) utilizing Rose Bengal as a catalyst, through a combined experimental and theoretical approach. Experiments validated the successful conversion of CO2 to CO in a homogeneous aqueous solution system under light irradiation, without additional photosensitizers or sacrificial agents. Theoretically, the DFT/TDDFT calculations modeled the catalyst-reactants as a hydrogen-bonded complex (HBC), understanding the energy, hydrogen, and electron transfer mechanisms induced by excited-state hydrogen bonding. Combining the photophysical and photochemical insights revealed the complete catalytic cycle, identifying the water oxidation process as the rate-limiting step in the entire photocatalytic CO2RR process. Experimental and computational results provide molecular-level insights into the structure–activity relationships. This work enhances comprehension of the pivotal role of excited-state hydrogen bonding and holds significant reference value for enhancing the conversion efficiency in the photocatalytic CO2RR. [ABSTRACT FROM AUTHOR]

Glycolaldehyde, a C2 compound, is the simplest sugar molecule, but whether it inherently exists in plants remains unclear due to its complicated existence form in different reaction conditions. By combination of a one-step chemical derivation method and high-performance liquid chromatography-mass spectrometry (HPLC-MS) measurements, herein, we clarify that the glycolaldehyde monomer molecule exists in aqueous media. Consequently, we report, for the first time, the identification of glycolaldehyde in various green plants such as Chlorella, spinach, maize, and Aeonium decorum f. variegate of the genus Aeonium. The present study provides direct evidence for the determination of glycolaldehyde and enriches our understanding of the chemical processes of biological metabolism in the plant kingdom. [ABSTRACT FROM AUTHOR]

Glycolaldehyde (HOCH2CHO, GA), the simplest molecule containing both hydroxyl and aldehyde groups, is structurally the most elementary member of monosaccharide sugars, which may provide new clues for probing the origin of life on planets like the Earth. Uncovering the existing state of GA in solution systems is an important scientific issue. Generally, methanol is used as the main mobile phase in the liquid chromatography analysis of GA, but the state of GA existing in methanol solution remains unknown, thus making it difficult to analyse GA accurately. Herein, the state and dynamic equilibrium of GA in methanol solution were systematically studied by UV-visible spectroscopy, nuclear magnetic resonance (1H-NMR) spectroscopy, liquid chromatography mass spectrometry (LC–MS) and density functional theory (DFT) calculations. The results demonstrated that the equilibrium component of GA in methanol solution is different from that in aqueous solution and that glycolaldehyde hemiacetal (GAHA) is a dominant component (>90%). Laying the foundation for experimental analysis, the transformation of different components at equilibrium was studied using DFT. The results confirm that hydrogen bonding-induced proton transfer occurs between the components at equilibrium. This work provides an important reference for the analysis of sugars and related compounds in various biochemical reactions. [ABSTRACT FROM AUTHOR]

In chemical industrial process, conversion of alkenes to functional oxygenates plays a key role in bridging between the feedstock and downstream application. Traditionally, the oxidation required highly‐active oxygen sources or molecular oxygen under high temperature and pressure. This poses challenges to the green and safe production of oxygenates. To circumvent the issues of massive consumption of fossil fuel and serious CO2 footprints, approaches of electro‐oxidation are developed under ambient conditions, adopting O2 and H2O as oxygen source. Utilizing electricity from renewable resources and the involved electron transfer, the performance is closely related to the interface characteristics of electrodes and electrolytes. This review presents the progress in catalysts design, electrolytes optimization, cells integration to effectively regulate the microenvironment of the interfaces. Further discussion of the mechanism analysis and potential issues are emphasized, based on the in‐situ characterization techniques, isotopic experiments and quenching tests. We hope this review can provide an outline for green approaches to oxidation of alkenes via electrocatalytic pathways. [ABSTRACT FROM AUTHOR]

The surface phonon polaritons (SPhPs) of SiC nanorods with different size and shape were studied using the scanning transmission electron microscopy – electron energy loss spectroscopy with both high spatial resolution and high energy resolution. The SPhP resonance energy depends on the nanorod diameter, and thus SPhPs can be controllably modulated by the geometric shape. Surface phonon polaritons (SPhPs) are potentially very attractive for subwavelength control and manipulation of light at the infrared to terahertz wavelengths. Probing their propagation behavior in nanostructures is crucial to guide rational device design. Here, aided by monochromatic scanning transmission electron microscopy-electron energy loss spectroscopy technique, we measure the dispersion relation of SPhPs in individual SiC nanorods and reveal the effects of size and shape. We find that the SPhPs can be modulated by the geometric shape and size of SiC nanorods. The energy of SPhPs shows red-shift with decreasing radius and the surface optical phonon is mainly concentrated on the surface with large radius. Therefore, the fields can be precisely confined in specific positions by varying the size of the nanorod, allowing effective tuning at nanometer scale. The findings of this work are in agreement with dielectric response theory and numerical simulation, and provide novel strategies for manipulating light in polar dielectrics through shape and size control, enabling the design of novel nanoscale phonon-photonic devices. [ABSTRACT FROM AUTHOR]

An efficient two‐step synthesis for the conversion of biomass‐derived 5‐hydroxymethyl‐furfural (HMF) to a variety of N‐substituted 2‐hydroxymethyl‐5‐methylpyrroles was developed. In the first step, 1‐hydroxyhexane‐2,5‐dione (HHD) was obtained by hydrogenation of HMF and thereafter used in a Paal–Knorr reaction with a range of amines in the absence of catalyst at room temperature. The reaction could potentially be used as a click reaction. [ABSTRACT FROM AUTHOR]

This article describes a selective reduction of functionalized amides, including N-acyl amino esters and dipeptides, to the corresponding amines using simple [Rh(acac)(cod)]. The catalyst shows excellent chemoselectivity in the presence of different sensitive functional moieties. [ABSTRACT FROM AUTHOR]

Methylation of amines is a fundamental and commonly used reaction in organic synthesis. Many methods are known including various reductive methylations using formaldehyde, formic acid, or carbon dioxide in the presence of reductants. However, several of these methods suffer from limited substrate scope and chemoselectivity because of the different nucleophilicities of substrates. In this respect, the combination of carbonates and hydrosilanes is a valuable methylation source in the presence of Pt-based catalysts. This highly tunable method allows for methylation of both aromatic and aliphatic amines, and chemoselective methylation of aminoalcohols and diamines. Notably, the in situ-formed catalyst can also be used for the reduction of carbonates to methanol at room temperature. Mechanistic insights on intermediates formed during the reaction pathway were obtained by using ESI mass spectrometry. [ABSTRACT FROM AUTHOR]

Efficient reduction of the tertiary amide bond in amino acid derivatives and peptides is described. Functional group selectivity has been achieved by applying a commercially available rhodium precursor and bis(diphenylphosphino)propane (dppp) ligand together with phenyl silane as a reductant. This methodology allows for specific reductive derivatization of biologically interesting peptides and offers straightforward access to a variety of novel peptide derivatives for chemical biology studies and potential pharmaceutical applications. The catalytic system tolerates a variety of functional groups including secondary amides, ester, nitrile, thiomethyl, and hydroxy groups. This convenient hydrosilylation reaction proceeds at ambient conditions and is operationally safe because no air-sensitive reagents or highly reactive metal hydrides are needed. [ABSTRACT FROM AUTHOR]

Efficient reduction of the tertiary amide bond in amino acid derivatives and peptides is described. Functional group selectivity has been achieved by applying a commercially available rhodium precursor and bis(diphenylphosphino)propane (dppp) ligand together with phenyl silane as a reductant. This methodology allows for specific reductive derivatization of biologically interesting peptides and offers straightforward access to a variety of novel peptide derivatives for chemical biology studies and potential pharmaceutical applications. The catalytic system tolerates a variety of functional groups including secondary amides, ester, nitrile, thiomethyl, and hydroxy groups. This convenient hydrosilylation reaction proceeds at ambient conditions and is operationally safe because no air-sensitive reagents or highly reactive metal hydrides are needed. [ABSTRACT FROM AUTHOR]

The 'green' reduction of carboxylic acids to alcohols is a challenging task in organic chemistry. Herein, we describe a general protocol for generation of alcohols by catalytic hydrogenation of carboxylic acids. Key to success is the use of a combination of Ru(acac)3, triphos and Lewis acids. The novel method showed broad substrate tolerance and a variety of aliphatic carboxylic acids including biomass-derived compounds can be smoothly reduced. [ABSTRACT FROM AUTHOR]

The 'green' reduction of carboxylic acids to alcohols is a challenging task in organic chemistry. Herein, we describe a general protocol for generation of alcohols by catalytic hydrogenation of carboxylic acids. Key to success is the use of a combination of Ru(acac)3, triphos and Lewis acids. The novel method showed broad substrate tolerance and a variety of aliphatic carboxylic acids including biomass-derived compounds can be smoothly reduced. [ABSTRACT FROM AUTHOR]

Ethers are of fundamental importance in organic chemistry and they are an integral part of valuable flavors, fragrances, and numerous bioactive compounds. In general, the reduction of esters constitutes the most straightforward preparation of ethers. Unfortunately, this transformation requires large amounts of metal hydrides. Presented herein is a bifunctional catalyst system, consisting of Ru/phosphine complex and aluminum triflate, which allows selective synthesis of ethers by hydrogenation of esters or carboxylic acids. Different lactones were reduced in good yields to the desired products. Even challenging aromatic and aliphatic esters were reduced to the desired products. Notably, the in situ formed catalyst can be reused several times without any significant loss of activity. [ABSTRACT FROM AUTHOR]

Ethers are of fundamental importance in organic chemistry and they are an integral part of valuable flavors, fragrances, and numerous bioactive compounds. In general, the reduction of esters constitutes the most straightforward preparation of ethers. Unfortunately, this transformation requires large amounts of metal hydrides. Presented herein is a bifunctional catalyst system, consisting of Ru/phosphine complex and aluminum triflate, which allows selective synthesis of ethers by hydrogenation of esters or carboxylic acids. Different lactones were reduced in good yields to the desired products. Even challenging aromatic and aliphatic esters were reduced to the desired products. Notably, the in situ formed catalyst can be reused several times without any significant loss of activity. [ABSTRACT FROM AUTHOR]

The anthropogenic managements of forest have created a network of roads resulting in the loss and alternation of habitat. To better understand road's impact on animal habitats, we assessed the habitat pattern of sables ( Martes zibellina), one of rodents within national first-class protected species, when roads are considered in Huzhong area in Da Hinggan Mountains, northeastern China. Employing published literatures about behavior ecology, aerial photographs and forest stand maps, we classified the study area into three habitat types including best-suitable, suitable and unsuitable habitats based on sable habitat requirements at the landscape scale including four variables derived from forest source map with attribute database. Results indicated the loss and significant fragmentation of best-suitable habitat and home range habitat when roads, especially 150 m avoidance distance of roads, were considered. The roads reduced and fragmented highly suitable habitats more significantly during earlier development period than the later development period. Additionally, the suitable area percentage increased with increasing distance to roads. This study helped to identify the suitable area for sables and location of sable population. Also, this study suggested the passage construction and road management involving road closure and removal will reduce the fragmentation functionally and benefit the sable population. [ABSTRACT FROM AUTHOR]

Formation of C-C bonds from CO2 is a much sought after reaction in organic synthesis. To date, other than C-H carboxylations using stoichiometric amounts of metals, base, or organometallic reagents, little is known about C-C bond formation. In fact, to the best of our knowledge no catalytic methylation of C-H bonds using CO2 and H2 has been reported. Described herein is the combination of CO2 and H2 for efficient methylation of carbon nucleophiles such as indoles, pyrroles, and electron-rich arenes. Comparison experiments which employ paraformaldehyde show similar reactivity for the CO2/H2 system. [ABSTRACT FROM AUTHOR]

Formation of C-C bonds from CO2 is a much sought after reaction in organic synthesis. To date, other than C-H carboxylations using stoichiometric amounts of metals, base, or organometallic reagents, little is known about C-C bond formation. In fact, to the best of our knowledge no catalytic methylation of C-H bonds using CO2 and H2 has been reported. Described herein is the combination of CO2 and H2 for efficient methylation of carbon nucleophiles such as indoles, pyrroles, and electron-rich arenes. Comparison experiments which employ paraformaldehyde show similar reactivity for the CO2/H2 system. [ABSTRACT FROM AUTHOR]

Background: Paired box 6 (PAX6), a highly conserved transcriptional factor, has been implicated in tumorigenesis. Aim: We aimed to explore the roles and molecular mechanisms of PAX6 and microRNA (miR-7) in colorectal cancer cells. Methods: Tissue microarray immunohistochemistry and Western blot were applied to examine the PAX6 expression. Real-time RT-PCR and Western blot were performed to determine the expression of miR-7 and PAX6. Luciferase reporter assay was used to determine whether PAX6 was a target of miR-7. Effects of miR-7 and PAX6 on colorectal cell proliferation, cell cycle progression, colony formation and invasion were then investigated. Western blot was used to determine the activities of the ERK and PI3K signal pathways, as well as the protein expression of MMP2 and MMP9. Results: The protein levels of PAX6 were gradually increased, while the expression of miR-7 was gradually reduced with malignancy of colorectal cancer. PAX6 was further identified as a target of miR-7, and its protein expression was negatively regulated by miR-7 in human colorectal cancer cells. Overexpression of PAX6 in Caco-2 and SW480 cells enhanced cellular proliferation, cell cycle progression, colony formation, and invasion, while miR-7 upregulation repressed these biological processes. Furthermore, the activities of ERK and PI3K signal pathways, as well as the protein levels of MMP2 and MMP9, were upregulated in PAX6-overexpressed Caco-2 and SW480 cells but deregulated in miR-7-overexpressed Caco-2 and SW480 cells. Conclusions: Our study suggests that as a novel target of miR-7, PAX6 may serve as a promising therapeutic target for colorectal cancer. [ABSTRACT FROM AUTHOR]

The authors focus on the methylation of amines with carbon dioxide and hydrogen molecule (H2). They mention that two catalysts formed from ruthenium acetylacetonate [Ru(acac)3] and 1,1,1-tris(diphenylphosphinomethyl) ethane, enabled the conversion of carbon dioxide and carboxylic acid derivatives into N,N-dimethylaniline and N-methylaniline. They mention that methylation reaction with formamide and methanol formed intermediates, which then reduced to a methylated product.

Not a ‘B'ore! Benzothiophene‐based boronic acids catalyze the reduction of tertiary, secondary, and primary amides in the presence of a hydrosilane. The reaction demonstrates good functional‐group tolerance. [ABSTRACT FROM AUTHOR]

Vielseitig und metallfrei: Benzothiophen ‐ Boronsäuren katalysieren die Reduktion tertiärer, sekundärer und primärer Amide durch ein Hydrosilan. In der Reaktion wird eine Vielzahl von funktionellen Gruppen toleriert. [ABSTRACT FROM AUTHOR]

Putting CO2 to work: Carbon dioxide is shown to be a general and selective methylating reagent for secondary and primary, aromatic and aliphatic amines under reductive conditions. A variety of tertiary amines are obtained from CO2 and commercially available silanes in high yields with good tolerance to nitrile, olefin, ether, ester, and hydroxy groups. [ABSTRACT FROM AUTHOR]

Kohlendioxid kann zur selektiven reduktiven Methylierung sekundärer und primärer aromatischer und aliphatischer Amine verwendet werden. Vielfältige tertiäre Amine werden durch Einwirkung von CO2 und käuflichen Silanen in hohen Ausbeuten erhalten. Die Katalysereaktion toleriert Nitril ‐ , Olefin ‐ , Ether ‐ , Ester ‐ und Hydroxygruppen in den Substraten. [ABSTRACT FROM AUTHOR]

Two irons for a smoother finish: An NAD(P)H model was regenerated readily in situ by iron‐catalyzed reduction with molecular hydrogen. The subsequent biomimetic reduction of α‐keto‐/ α‐iminoesters proceeded smoothly in the presence of an iron‐based Lewis acid (LA) to provide α‐hydroxyesters and amino acid esters in good to excellent yields (see scheme; NAD(P)+=nicotinamide adenine dinucleotide (phosphate), TM=transition metal). [ABSTRACT FROM AUTHOR]

Zwei Eisenspezies im Team: Ein NAD(P)H ‐ Modell wird in einer eisenkatalysierten Reduktion mit molekularem Wasserstoff in situ regeneriert. Die anschließende biomimetische Reduktion von α ‐ Keto ‐ und α ‐ Iminoestern liefert in Gegenwart einer Eisen ‐ basierten Lewis ‐ Base (LA) α ‐ Hydroxy ‐ bzw. α ‐ Aminosäureester in guten bis exzellenten Ausbeuten (siehe Schema; NAD(P)+=Nicotinamidadenindinucleotid(phosphat), TM=Übergangsmetall). [ABSTRACT FROM AUTHOR]

The epoxidation of olefins with methyltrioxorhenium (MTO) in the presence of various chiral oxazolines and pyridinebis(oxazoline) ligands as well as achiral N-ligands has been investigated. By applying 1-octene as a model system, reaction conditions were optimized, and high yields and good chemoselectivity (>90 %) were achieved. By applying other aromatic and aliphatic olefins, similar chemoselectivities and up to 19 % enantioselectivity were obtained. [ABSTRACT FROM AUTHOR]

Abstract: It is well recognized that harsh outer space environment, consisting of microgravity and radiation, poses significant health risks for human cells. To investigate potential effects of the space environment exposure on cancer cells we examined the biological changes in Caski cells carried by the “Shen Zhou IV” spaceship. After exposure for 7 days in spaceflight, 1440 survival subclonal cell lines were established and 4 cell lines were screened. 44F10 and 17E3 were selected because of their increased cell proliferation and tumorigenesis, while 48A9 and 31F2 had slower cytological events. Experiments with cell proliferation assay, flow cytometry, soft agar assay, tumorigenesis assay and DNA microarray analysis have shown that selected cell lines presented multiple biological changes in cell morphology, cell growth, tumorigenicity and gene expression. These results suggest that space environment exposure can make significant biological impact on cancer cells and provide an entry point to find the immunological target of tumorigenesis. [Copyright &y& Elsevier]

[Display omitted] • CQDs were synthesized via coal tar pitch with ozone oxidation method. • The method provides advantages of low-cost, convenience, and environmentally attractive. • CQDs showed a highly sensitivity and selectivity in detection of Fe3+ ions. • CQDs can be used in fluorescence imaging of cells. Carbon quantum dots (CQDs) emerging as newcomers of carbon nanoparticles exhibit fascinating electro-optical properties, and thereby have been widely used in many fields. Herein, we present a new facile, economical and environmentally attractive strategy for the preparation of CQDs via one-step ozone (O 3) treatment of coal tar pitch (CTP). CQDs prepared by this approach exhibit a narrow size distribution between 3–7 nm, and CQDs with a diameter of 4.8 nm accounts for approximately 42.8 %. CQDs were investigated as fluorescent probes for the detection of metal ions, and demonstrated highly sensitive and selective detection of Fe3+ ions. A calibration curve displayed a linear response over the range of 0–9 μM and a detection limit of 0.02 μM (1.12 ppb). Moreover, the photoluminescence performance of the CQDs/Fe3+ complex could be recovered with the addition of EDTA, indicating a great potential for applications of this unique fluorescent CQDs in the detection of Fe3+. Finally, the experiments of CQDs in cell imaging confirmed that the CQDs can be used as potential fluorescent probes in biological imaging, cell labeling with strong luminescence and low toxicity. [ABSTRACT FROM AUTHOR]

Oxide ceramic particle-reinforced iron-based composites showed excellent abrasive wear resistance; however, the weak bonding property of the interfacial layer limited the application in harsh severe conditions. The combination of electroless plating (CVD) and multiarc ion plating technologies (PVD) was used to prepare Ni/Cr coatings on the surface of the ZTA ceramics, which effectively improves the interface bonding properties of the ZTAP/Fe composites. The interface of iron matrix composites reinforced by bare ZTA ceramic particles presented visible holes and crevices. After introducing Ni/Cr coating, a continuous and tight transition layer occurred at the interface between the ZTA ceramics and the Cr15 matrix. The diffusion and reaction of Ni and Cr nearby the interface caused a metallurgical bonding of composites. Abrasive wear and slurry erosion behavior of the ZTAP/Fe composites assisted with the metallic coatings was systematically investigated. The results indicated that the transition layer of the composites could effectively resist the removal and corrosion in the slurry fluids. Furthermore, the solid solution of Cr in the iron matrix improved the corrosion resistance of the Cr15 matrix in the artificial seawater medium. The ZTA ceramics and the Cr15 matrix were simultaneously cut under the SiC abrasive during two-body abrasive wear. ZTA ceramic particles play a protective role in the iron matrix due to their high hardness and excellent toughness. [ABSTRACT FROM AUTHOR]

Despite of high conductivity and reducing ability, transition metal nanoparticles tend to aggregate and unavoidably impact the selectivity during the proton‐coupled reduction process of CO2RR. New strategy to regulate and utilize the electronic property of transition‐metal particles allows for effective tuning of eCO2RR activity. Through simple creation of N‐doped carbon shells surrounding Ni nanoparticles and controlling the amount and arrangement of the N atoms, successful and long‐lasting electrochemical reduction of CO2 was accomplished. The inherent HER activity was almost completely suppressed. It exhibited FECO above 90 % in a 500 mV potential window, with the optimal up to 96.5 % at −0.78 V vs RHE. In flow cell electrolysis, a current density of 289.4 mA/cm2 was achieved with Faradic efficiency of 96.4 % towards CO. The results of control experiments using different catalysts imply that electron transfer between Ni core and shells was significantly influenced by the property of N atoms. High content of graphitic nitrogen is crucial for the catalytic performance. [ABSTRACT FROM AUTHOR]

On the way to a green carbon cycle: Ding and co‐workers developed the highly efficient catalyst 1 for the hydrogenation of cyclic carbonates to diols and methanol (TON up to 87 000) by modification of the industrially applied omega process. [ABSTRACT FROM AUTHOR]

Simple Summary: Estimation of population abundance or density is necessary for managing deer populations. However, there is no estimation of Siberian roe deer (Capreolus pygargus) in the Lesser Xing'an Mountains, northeast China where the density of roe deer is much lower than that of European or North American populations. We used fecal-DNA capture-mark-recapture to estimate the abundance and density in Liangshui National Nature Reserve. We collected 422 fecal pellet groups during two sampling periods in 2016, identified them to be 77 individuals by the DNA microsatellite technique and estimated the abundance of roe deer to be 87 deer (80–112, 95% CI) using the Program CAPTURE. Density was estimated to be 2.9 deer/km2 (2.7–3.7, 95% CI). Our study estimated the roe deer population abundance by a feces-based capture-mark-recapture approach in northeast China, successfully demonstrating the applicability of this feces sampling method in monitoring deer populations in this area. It also contributes to the development of low-density deer population ecology and management. It is necessary to estimate the population abundance of deer for managing their populations. However, most estimates are from high-density populations inhabiting the forests of North America or Europe; there is currently a lack of necessary knowledge regarding low-density deer populations in different forest habitats. In this article, we used fecal DNA based on the capture-mark-recapture method to estimate the population abundance of Siberian roe deer (Capreolus pygargus) in Liangshui National Nature Reserve in the Lesser Xing'an Mountains, northeast China, where the deer population was found to be of a low density by limited studies. We used a robust survey design to collect 422 fecal pellet groups in 2016 and extracted DNA from those samples, generating 265 different genotypes; we thus identified 77 deer individuals based on six microsatellite markers (Roe1, Roe8, Roe9, BM757, MB25 and OarFCB304). With capture and recapture records of these 77 individuals, the abundance of roe deer was estimated to be 87 deer (80–112, 95% CI) using the Program CAPTURE. Using an effective sampling area which resulted from the mean maximum recapture distance (MMRD), we converted the population abundance to a density of 2.9 deer/km2 (2.7–3.7, 95% CI). Our study estimated the roe deer population abundance by a feces-based capture-mark-recapture approach in northeast China, successfully demonstrating the applicability of non-invasive genetic sampling in monitoring populations of deer in this area, which contributes to the development of low-density deer population ecology and management. [ABSTRACT FROM AUTHOR]

New polyhydroxy ionic polymers were designed and prepared to heterogeneously catalyze CO2 cycloaddition reaction with complete chemoselectivity and up to 99 % yields. Using copolymer of 1‐(2‐hydroxyl‐ethyl)‐3‐vinyl‐imidazolium bromide ([HeVim][Br]) and styrene, the highest yield of propylene carbonate was obtained. And, it is significantly higher than that obtained with the same amount of hydroxy monomer [HeVim][Br] (only 24 % yield), thus showing the concerted promotion effect of polyhydoxyl groups during ring opening of epoxides. The catalyst presented excellent recycling performance (10 cycles). Various terminal cyclic carbonates were synthesized with above 95 % yields. A synergistic function of hydroxyl group as efficient hydrogen bonding donor and bromide anion as nucleophilic agent was put forward. [ABSTRACT FROM AUTHOR]

Domain walls are of increasing interest in ferroelectrics because of their unique properties and potential applications in future nanoelectronics. However, the thickness of ferroelastic domain walls remains elusive due to the challenges in experimental characterization. Here, we determine the atomic structure of ferroelastic domain walls and precisely measure the polarization and domain wall thickness at picometer scale using annular bright field imaging from an aberration-corrected scanning transmission electron microscope. We find that the domain wall thickness in PbZr 0.2 Ti 0.8 O 3 and PbTiO 3 thin films is typically about one unit cell, across which the oxygen octahedron distortion behavior is in excellent agreement with previous first-principles calculations. Remarkably, wider domain walls about two unit cells in thickness are also observed for those domains walls are coupled with dislocations and underwent a compressive strain. These results suggest that the thickness of ferroelastic domain walls highly depends on their atomic environments. This study can help us to understand the past debatable experimental results and provide further insights into control of domain wall thickness via strain engineering for their possible applications in nanoelectronics. Image, graphical abstract [ABSTRACT FROM AUTHOR]

The title reaction proceeds successfully with the simple catalyst Rh(cod)(acac) which reveals an excellent chemoselectivity in the presence of various sensitive functional groups. [ABSTRACT FROM AUTHOR]

A diagram of the chemical structure is presented which shows reductive methylation of amines using carbonates.

The catalyst, which consists of iron oxides surrounded by nitrogen-doped-graphene shells immobilized on carbon, is obtained via pyrolysis of iron acetate and phenanthroline followed by a selective leaching process. [ABSTRACT FROM AUTHOR]

A highly selective reduction of N-acylated amino acid derivatives to the corresponding N-alkylated products is developed using PhSiH3 in the presence of a Rh(II)-catalyst. [ABSTRACT FROM AUTHOR]

Aryl, benzyl, and alkylcarboxylic acids endowed with a range of functional groups as well as dicarboxylic acids are efficiently reduced to the corresponding alcohols. [ABSTRACT FROM AUTHOR]

A molecular diagram is presented of Lewis acid induced ruthenium(II)-catalyzed etherifications by carboxylic acids or esters' selective hydrogenation.

Cerium and boron are commonly used components to tune the acidic/basic property of catalysts in industry. In this work, cerium or boron‐doped copper‐based catalysts (xM−Cu/SiO2, M=Ce/B) were prepared with the ammonia‐evaporation method. Both X‐ray diffraction and Auger electron spectroscopy revealed that Cu+ content increased along with the Ce‐doping, but decreased by B‐doping. NH3‐Temperature Program Desorption results showed no change in the acidity of Ce‐doped catalysts, while significant amounts of medium‐strong acid sites appeared after B‐doping. Application in ethylene carbonate hydrogenation indicates the promoting role of Ce‐dopant in methanol production, while boron exhibits negative effects. The significant difference can be attributed to distinctive acidic/basic properties of Ce/B dopants, which affect the interaction between Cu and Si in the precursors, and thus adjust the ratio of Cu+/(Cu++Cu0). [ABSTRACT FROM AUTHOR]

[Display omitted] • Well-defined cyclic carbamoyl-Mn(I) complexes are prepared with improved stability. • Carbamoyl-Mn(I) accelerates alkenes epoxidation via Mn(III)=O and Mn(II)-O species. • CO 2 cycloaddition of epoxides was promoted by acidic N–H proton in carbamoyl unit. There is no precedent for the usage of transition metal carbamoyl complexes (typical hydrogenase models) as pre-catalysts for oxidation or CO 2 utilization purposes. In this work, we describe that carbamoyl-Mn(I) complexes are capable of selectively catalyzing both epoxidation of olefins and epoxides with carbon dioxide to form cyclic carbonates. The dual-role catalytic system was well adapted to a wide range of aromatic olefins, and the desired cyclic carbonates were obtained in moderate to excellent yields. Mechanistic investigations indicated that active Mn(II)-oxo and Mn(III)-oxo species were involved in the oxidation process. [ABSTRACT FROM AUTHOR]

An abstract of the article "Relay Iron/Chiral Broensted Acid Catalysis: Enantioselective Hydrogenation of Benzoxazinones" by L.-Q. Lu and colleagues is presented.

The article presents chemical equations related to the article "Selective Methylation of Amines with Carbon Dioxide and H2" by Y Li and others published in the periodical "Angewandte Chemie International Edition" in 2013.

A general method for the hydrogenative deoxygenation of tertiary, secondary, and primary amides into the corresponding amines is developed. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "A General Catalytic Methylation of Amines Using Carbon Dioxide" by Y. Li and colleagues, published in the periodical "Angewandte Chemie International Edition" in 2013.

This method uses dual iron catalysis for the title reaction. [ABSTRACT FROM AUTHOR]

Precise control of the coordination structure of metal centers is an ideal approach to achieve reasonable selectivity, activity, and stability in the electrochemical reduction of CO2. In this work, the KOH activation strategy for preparation of hierarchically porous material containing Ni single‐atoms with axial‐oxygen coordination is reported. Spectroscopic measurements reveal the multiple roles of KOH as oxygen source, pore‐making reagent and promoter for the formation of key phthalocyanine structure. It exhibits superior surface area (1801 m2 g−1) and electrocatalytic performance (Faradaic efficiency of 94%, Turnover frequency of 11 362 h−1). Notably, KOH‐enabled architecture with abundant pores benefits the anchoring of Ni atoms and mass transfer for high activity and selectivity. Density functional theory calculations suggest that the axial‐oxygen ligand can promote the electronic delocalization of the Ni site for facilitating the *COOH formation and *CO desorption to efficiently produce CO. [ABSTRACT FROM AUTHOR]

A new, mild, and chemoselective method for the conversion of phosphine oxides into phosphines is reported. [ABSTRACT FROM AUTHOR]