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Emerging countries are at the frontier of climate change actions, and carbon emissions accounting provides a quantifiable measure of the environmental impact of economic activities, which allows for comparisons of emissions across different entities. However, currently there is no study covering detailed emissions inventories for emerging countries in Central Asian. This paper compiles detailed and accurate carbon emissions inventories in several Central Asian countries (i.e., Kazakhstan, Kyrgyzstan, Pakistan, Palestine, Tajikistan, and Uzbekistan) during the period 2010–2020. Using the IPCC administrative territorial approach, we for the first time compile their emissions inventories in 47 economic sectors and five energy categories. Moreover, we also investigate decoupling status based on Tapio decoupling model and examine emissions driving factors based on the index decomposition analysis method. The primary results illustrate that carbon emissions in Central Asian countries are increasing with huge differences. Decoupling results highlight that most of the sample countries still need more effort to decouple the economy and emissions except that Pakistan achieves an ideal strong decoupling state. The results of the decomposition indicate that the economy and population both raise emissions, while energy intensity and carbon intensity are negative drivers in some countries. We propose practical policy implications for decarbonization and energy transition roadmap in Central Asian countries. [ABSTRACT FROM AUTHOR]

Poly(ethylene oxide)-based solid-state electrolytes are widely considered promising candidates for the next generation of lithium and sodium metal batteries. However, several challenges, including low oxidation resistance and low cation transference number, hinder poly(ethylene oxide)-based electrolytes for broad applications. To circumvent these issues, here, we propose the design, synthesis and application of a fluoropolymer, i.e., poly(2,2,2-trifluoroethyl methacrylate). This polymer, when introduced into a poly(ethylene oxide)-based solid electrolyte, improves the electrochemical window stability and transference number. Via multiple physicochemical and theoretical characterizations, we identify the presence of tailored supramolecular bonds and peculiar morphological structures as the main factors responsible for the improved electrochemical performances. The polymeric solid electrolyte is also investigated in full lithium and sodium metal lab-scale cells. Interestingly, when tested in a single-layer pouch cell configuration in combination with a Li metal negative electrode and a LiMn0.6Fe0.4PO4-based positive electrode, the polymeric solid-state electrolyte enables 200 cycles at 42 mA·g−1 and 70 °C with a stable discharge capacity of approximately 2.5 mAh when an external pressure of 0.28 MPa is applied. Solid-state polymer electrolytes are crucial for developing future rechargeable batteries, but they are still limited in performance. Here, the authors designed a topological polymeric solid electrolyte, enabling an all-solid-state high-voltage lithium metal pouch cell to cycle 200 times efficiently. [ABSTRACT FROM AUTHOR]

1-Butene polymerizations were carried out by using a MgCl/TiCl/ID-AlR/ED catalyst system in n-hexane, therein the internal donor (ID) is diisobutyl phthalate (DIBP), the external donor (ED) is diphenyl dimethoxysilane (DDS) or cyclohexyl methyl dimethoxysilane (CHMMS), and the AlR activator is AlEt or Al( i-Bu). The effect of the molar ratio of DIBP/Mg and polymerization conditions on the catalytic activity and the isotactic index (II) of poly(1-butene) (PB) was investigated. The dosage of DIBP remarkably improved the catalytic activity and the II of PB. CHMMS was more effective than DDS for increasing the II of PB. The addition of a small amount of hydrogen enhanced the catalytic activity from 15.1 to 17.5 kg-PB·gTi and the II value of PB from 89.3% to 95.1%. The mixture of AlR was beneficial to increase the catalytic activity with negligible effect on the isospecificity. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

In this study, a series of imidazolium-based ionic liquids (ILs) having carboxylic acid moieties were synthesized and used as new homogeneous catalysts to synthesize cyclic carbonates from CO and epoxides. Even in the absence of any co-catalyst and organic solvent, carboxylic-acid-functionalized ILs showed better catalytic activity in the coupling reaction of CO and styrene oxide for the production of styrene carbonate than did hydroxyl-functionalized ILs and conventional ILs without any functional moieties. A detailed investigation was carried out on a variety of factors that affected the reactivity, such as the alkyl chain length and the molecular composition of IL molecules including the halide ions. The effect of various reaction parameters such as reaction time, temperature, CO pressure and catalyst amount was also investigated in detail. The mechanism underlying the enhanced rate of the cycloaddition reaction in the presence of carboxylic-acid-functionalized ILs was proposed. [ABSTRACT FROM AUTHOR]

Poly(5-ethylidene-2-norbornene) (PENB) was synthesized via a vinylic pathway using a cationic palladium-based catalyst, displaying high activity up to 1.06×10 g-PENB/mol Pd. The effects of the monomer to catalyst ratio, temperature, reaction time, and concentration on the polymerization were investigated systematically. The control tests and spectroscopic analyses of the PENB indicate that 5-ethylidene-2-norbornene is polymerized via an addition polymerization using endocyclic double bonds. The post-modification was also performed using a free radical graft polymerization. The resulting PENB copolymers were characterized by IR, H NMR, and GPC analyses. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A series of aluminum complexes supported by β-ketoamino, ligand-bearing, 3-position substituents LAlEt (L=CHC(O)C(Cl)=C(CH)NAr ( L ), L=CHC(O)C(H)=C(CH)NAr ( L ), L=CHC(O)C(Ph)=C(CH)NAr ( L ), and L=CHC(O)C(Me)=C(CH)NAr ( L ), Ar=2,6-PrCH) were synthesized in situ and employed in the ringopening polymerization (ROP) of ε-caprolactone (ε-CL) and cyclohexene oxide (CHO). The 3-position substituents on the β-ketoamino ligand backbone of the aluminum complexes influenced the catalyst activity remarkably for both ROP of ε-CL and CHO. Aluminum β-ketoamino complexes displayed different catalytic behavior in ROP of ε-CL and CHO. The order of the catalytic activity of LAlEt was L AlEt> L AlEt> L AlEt> L AlEt for ROP of ε-CL, being opposite to the electron-donating ability of the 3-position substituents on the β-ketoamino ligand, while the order of the catalytic activity for ROP of CHO was L AlEt> L AlEt> L AlEt> L AlEt. The effects of reaction temperature and time on the ROP were also investigated for both ε-CL and CHO. [ABSTRACT FROM AUTHOR]

Poly(norbornene dimethyl dicarboxylate)s, (PNDMD)s, were prepared by addition polymerization with palladium(II) catalyst from pure exo-monomers, and their structure and properties were compared with those of poly(norbornene dicarboxylic acid dialkyl ester)s, (PNDADA)s. Both polymer series exhibited good solubility in general organic solvents and excellent thermal stability up to 330 °C. Wide-angle X-ray scattering (WAXS) study indicated the presence of nano-scale layer-like order in amorphous PNDADAs, while PNDMDs showed random amorphous structure. The glass transition temperatures and dielectric constants of solid polymers were found to decrease as the alkyl side-chain length increases for both polymer series. However, PNDMDs showed lower glass transition temperatures and higher dielectric constants, as compared with those of PNDADAs containing the same alkyl substituents. This difference, caused by the higher side-group mobility of PNDMDs, may be closely related to the nano-scale order in amorphous PNDADAs and its absence in PNDMDs. [ABSTRACT FROM AUTHOR]

[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A coordination polymer (CP) based nanoprobe is described for colorimetric and fluorometric (dual mode) determination of ferric ion. The method is making use of a nanosized Gd(III)−5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin coordination polymer that was prepared by a single-step hydrothermal procedure. The nanoprobe is monodisperse and has uniform size and good water solubility. It also exhibits strong fluorescence and magnetic resonance response. On exposure to Fe(III), the color of the solution changes from red to brown as the concentration of Fe(III) exceed 5 μM. Similarly, the red fluorescence of the probe (with excitation/emission peaks at 420/675 nm) decreases as concentrations of Fe(III) increase from 0.5 to 100 μM. The limit of detection is 98 nM in the fluorometric mode. The assay was applied to the determination of Fe(III) in fetal bovine serum samples.Schematic presentation of the synthesis and application of lanthanide-porphyrin based coordination polymer for ferric ion detection in colorimetric and fluorometric dual modes. [ABSTRACT FROM AUTHOR]