GHGs and air pollutants embodied in China’s international trade: Temporal and spatial index decomposition analysis

<div><p>Temporal index decomposition analysis and spatial index decomposition analysis were applied to understand the driving forces of the emissions embodied in China’s exports and net exports during 2002–2011, respectively. The accumulated emissions embodied in exports accounted for approximately 30% of the total emissions in China; although the contribution of the sectoral total emissions intensity (technique effect) declined, the scale effect was largely responsible for the mounting emissions associated with export, and the composition effect played a largely insignificant role. Calculations of the emissions embodied in net exports suggest that China is generally in an environmentally inferior position compared with its major trade partners. The differences in the economy-wide emission intensities between China and its major trade partners were the biggest contribution to this reality, and the trade balance effect played a less important role. However, a lower degree of specialization in pollution intensive products in exports than in imports helped to reduce slightly the emissions embodied in net exports. The temporal index decomposition analysis results suggest that China should take effective measures to optimize export and supply-side structure and reduce the total emissions intensity. According to spatial index decomposition analysis, it is suggested that a more aggressive import policy was useful for curbing domestic and global emissions, and the transfer of advanced production technologies and emission control technologies from developed to developing countries should be a compulsory global environmental policy option to mitigate the possible leakage of pollution emissions caused by international trade.</p></div

Free Radical Graft Copolymerization Strategy To Prepare Catechin-Modified Chitosan Loose Nanofiltration (NF) Membrane for Dye Desalination

In this study, a novel free radical graft copolymerization strategy was applied to prepare the catechin-modified chitosan loose nanofiltration (NF) membrane for dye desalination. First, catechin, the eco-friendly natural material, was grafted onto chitosan through a free radical reaction and self-cross-linking. Second, the catechin-grafted-chitosan conjugates were assembled onto the surface of the hydrolyzed polyacrylonitrile (HPAN) ultrafiltration (UF) membrane. Finally, the prepared membrane was characterized by FT-IR, XPS, SEM, AFM, electrokinetic analyzer, and contact angle goniometer. The results showed that the prepared membrane exhibited a high rejection for dyes (i.e., 99.6% for congo red, 98.7% for acid fuchsin, and 98.5% for crystal violet) and a low retention for inorganic salts (i.e., 4.8% for Na₂SO₄, 12.5% for NaCl, 15.8% for MgSO₄, and 16.2% for MgCl₂). The Na₂SO₄ rejection, especially, was 2–3 times lower than that of the reported loose NF membranes. Meanwhile, a high removal rate of 82% for NaCl with a dye loss rate of 10% was also observed in the constant-volume batch dye desalination process. Moreover, the membrane also possessed a good dye antifouling ability with a flux recovery ratio of 87.8% and an irreversible fouling ratio of 12.2%. Hence, this catechin-modified chitosan loose NF membrane shows a promising application for dye desalination

Whisper Gallery Modes in Monolayer Tungsten Disulfide-Hexagonal Boron Nitride Optical Cavity

There are strong interests in constructing nanolasers using two-dimensional transition metal dichalcogenides (TMDs) due to their strong light–matter interactions and high optical gain. However, most cavity designs based on transfer of exfoliated TMDs on silicon oxide are not optimized since monolayer emitters are located far from where the photonic mode reaches maximum intensity. By taking advantage of the excellent dielectric properties of hexagonal boron nitride (h-BN), we design a new microdisk optical cavity fabricated from a van der Waals (VdW) stacked h-BN/WS₂/h-BN. The heterostructure is patterned into microdisk cavities characterized by whispering gallery modes (WGMs). The emission intensity of the WS₂ trion is enhanced by 2.9 times that of exciton in the heterostructure, giving rise to whisper gallery modes with resonance intensities that show nonlinear power dependence. A Rayleigh scatterer directs the cavity emission to vertical collection. Such VdW heterostructure provides an atomically smooth interface that is ideal for low loss photon propagation, giving a <i>Q</i> factor of 1200

Supplementary document for Deep Learning Empowers Photothermal Microscopy with Super-Resolution capabilities - 6915268.pdf

network and simulation

In Vivo Neurochemical Monitoring Using Benzoyl Chloride Derivatization and Liquid Chromatography–Mass Spectrometry

In vivo neurochemical monitoring using microdialysis sampling is important in neuroscience because it allows correlation of neurotransmission with behavior, disease state, and drug concentrations in the intact brain. A significant limitation of current practice is that different assays are utilized for measuring each class of neurotransmitter. We present a high performance liquid chromatography (HPLC)–tandem mass spectrometry method that utilizes benzoyl chloride for determination of the most common low molecular weight neurotransmitters and metabolites. In this method, 17 analytes were separated in 8 min. The limit of detection was 0.03–0.2 nM for monoamine neurotransmitters, 0.05–11 nM for monoamine metabolites, 2–250 nM for amino acids, 0.5 nM for acetylcholine, 2 nM for histamine, and 25 nM for adenosine at sample volume of 5 μL. Relative standard deviation for repeated analysis at concentrations expected in vivo averaged 7% (<i>n</i> = 3). Commercially available ¹³C benzoyl chloride was used to generate isotope-labeled internal standards for improved quantification. To demonstrate utility of the method for study of small brain regions, the GABA_A receptor antagonist bicuculline (50 μM) was infused into a rat ventral tegmental area while recording neurotransmitter concentration locally and in nucleus accumbens, revealing complex GABAergic control over mesolimbic processes. To demonstrate high temporal resolution monitoring, samples were collected every 60 s while neostigmine, an acetylcholine esterase inhibitor, was infused into the medial prefrontal cortex. This experiment revealed selective positive control of acetylcholine over cortical glutamate