•A novel air-water based thermoelectric cooling unit is experimentally investigated.•Different climate conditions are simulated using of different air flow rates and temperatures.•Various parameters ...are evaluated to find optimum condition.•COP/COPmax is studied as a new consideration and memorable behavior was observed.
In this paper, the cooling feasibility of air flow via a novel air-water based TEC system (as an alternative air cooling unit) is experimentally investigated for different climate conditions. Contrary to previous studies, thermoelectric hot side temperature was adjusted by a low constant water flow rate (and not by an air fan) which significantly increased the cold side performance of TEM. Ten parameters including Ta,inlet, Tw,inlet, Ta,outlet, Tw,outlet, Tc, Ta, ṁa,ṁw and DC voltage and DC current were directly recorded by measurement instruments during the experiments. Six other parameters including qc, qh, COPc, COPmax, COPc/COPmax and qair were evaluated by formulas and correlations using of aforesaid measured data. Five numbers of aforementioned parameters were variant parameters. Indeed, the effect of ṁa,ṁw, DC voltage/current and Ta,inlet (variant parameters) on other impressionable parameters were investigated in present study. Optimum working condition was evaluated from a new point of view. Indeed, in this paper, it was accidently found out that, despite the descending behavior of both COPc and COPmax (due to changing of variants), the ratio of said parameters (COPc/COPmax) creates a peak point (ascending and then descending) in all cases. Said peak point can be considered as an appropriate working condition of thermoelectric units. Findings showed that, the cold side of thermoelectric system can act as an applicable air cooling system especially when the hot side of thermoelectric is cooled by a current liquid such as water.
Coat protein complex I (COP-I) mediates the retrograde transport from the Golgi apparatus to the endoplasmic reticulum (ER). Mutation of the COPA gene, encoding one of the COP-I subunits (α-COP), ...causes an immune dysregulatory disease known as COPA syndrome. The molecular mechanism by which the impaired retrograde transport results in autoinflammation remains poorly understood. Here we report that STING, an innate immunity protein, is a cargo of the retrograde membrane transport. In the presence of the disease-causative α-COP variants, STING cannot be retrieved back to the ER from the Golgi. The forced Golgi residency of STING results in the cGAS-independent and palmitoylation-dependent activation of the STING downstream signaling pathway. Surf4, a protein that circulates between the ER/ ER-Golgi intermediate compartment/ Golgi, binds STING and α-COP, and mediates the retrograde transport of STING to the ER. The STING/Surf4/α-COP complex is disrupted in the presence of the disease-causative α-COP variant. We also find that the STING ligand cGAMP impairs the formation of the STING/Surf4/α-COP complex. Our results suggest a homeostatic regulation of STING at the resting state by retrograde membrane traffic and provide insights into the pathogenesis of COPA syndrome.
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Despite the overwhelming advantages of high theoretical specific energy and low-cost, the realistic application of lithium-sulfur batteries is still restricted by the shuttle effect ...of intermediate polysulfides, low conductivity of sulfur and volume variation during charging and discharging. Tailored sulfur cathode is of significant importance for realizing high-performances. This study reports a carbon nanotube (CNT)-modified polar Co(PO3)2/CoP nanoparticles embedded nitrogen-doped porous-shell carbon polyhedron (CNT/CPO/CPNC-1) as a sulfur host to simultaneously overcome the barriers of lithium–sulfur batteries. The shuttle effect can be significantly restrained by the physical confinement of unique porous structure and the chemical adsorption/catalysis conversion of polar Co(PO3)2/CoP and the heteroatom doping of nitrogen. Meanwhile, the porous-shell carbon with interconnected carbon nanotubes can simultaneously provide a conductive framework, facilitate rapid electrical transport, and enable a large inner space to buffer volume expansion. As a result, CNT/CPO/CPNC-1/S cathode demonstrates an excellent reversible capacity of 1371.3 mAh g−1 at 0.1 C with stable Coulombic efficiency of 98% and an outstanding cycling stability with an ultralow capacity decay rate of 0.048% per cycle (500 cycles at 1.0 C). This work pioneers the employment of Co(PO3)2/CoP/carbon hybrid materials as sulfur host and sheds a new light to explore the high-performance lithium-sulfur batteries.
Hydrogen evolution reaction (HER), serving as the cathodic reaction of magnesium (Mg)/seawater battery, could not only produce clean hydrogen directly from seawater but also generate electricity. ...However, the kinetics of the hydrogen evolution directly from the neutral seawater is sluggish, and leads to unsatisfied HER and battery performance. Herein, a unique porous CoP/Co2P heterostructure electrode was fabricated via a template-free strategy. As demonstrated, the optimized porous CoP/Co2P heterostructure exhibits superior activity for HER, with low overpotential of 87, 133 and 454 mV at 10 mA cm−2 in acidic, alkaline and seawater media, respectively. An Mg/seawater battery fabricated with the porous CoP/Co2P heterostructure cathode displays promising performance, with a peak power density of 6.28 mW cm−2, approaching to the platinum cathode, and a satisfied stability in a 24 h stability test, which is the best non-noble metal cathode reported. The superior battery performance could be attributed to the large active interfaces and the high specific surface area of the porous CoP/Co2P heterostructure electrode, which guarantee a low polarization of the cathodic HER.
•The first demonstration of template-free synthesis porous CoP/Co2P heterostructure.•CoP/Co2P heterostructure is featured with porous structure and abundant interfaces.•CoP/Co2P heterostructure exhibits high HER and Mg/seawater battery performance.
•Cu3P@CoP composite photocatalyst was obtained by phosphating Cu-MOFs@ZIF-9(Co) at low temperature.•Cu3P@CoP composite photocatalyst has a self-supporting hierarchical 3D structure.•Construction of ...p-n-type heterojunction Cu-P@Co-P interface.•The built-in electric field of the p-n type heterojunction provides a fast electron transmission channel.
In this study, we developed a novel in situ growth scheme to construct the Cu-MOFs@ZIF-9(Co) core-shell precursor material. The Cu-MOFs@ZIF-9(Co) core-shell precursor was treated by low-temperature phosphorization to obtain a Cu3P@CoP composite catalyst with a self-supporting structure. Cu3P@CoP composite catalyst not only had a hierarchical structure, but also built a p-n heterojunction at the interface. The unique structure and composition of Cu3P@CoP could promote charge migration and provide large surface area and rich active sites to drive water photolysis. In addition, by controlling the degree of phosphation of Cu-MOFs@ZIF-9(Co) material and adjusting the ratio of Cu and Co, it was found that the maximum hydrogen-producing activity of the composite photocatalyst reached 469.95 μmol (9399 μmol h−1 g−1), and it had a very excellent cycle stability. The results of photoelectrochemical and fluorescence tests showed that the proper conduction and valence band positions of Cu3P and CoP formed a more effective path way for the thermodynamic charge transfer. The construction of p-n type heterojunction provided a fast electron transfer channel in the Cu-P@Co-P interface. The formed special structrue and the existence of the bult-in electric filed in the p-n heterojunction made the photogenerated carriers in the composite have more effective separation and lower recombination rate, which significantly enhanced H2 production activity. At the same time, our work will provide a new strategy for the rational design of efficient catalysts of MOFs derivatives and a new direction for the design of transition metal phosphide photocatalysts.
•CoP-HCCN composite was prepared by a simple solvothermal route.•The CoP-HCCN composites showed outstanding visible-light photocatalytic activity for degradation of TC.•The possible photodegradation ...pathways of TC over CoP-HCCN was proposed based on the intermediates detected by LC-MS.
Graphitic carbon nitride (g-C3N4) has been regarded as an emerging and promising semiconductor photocatalyst for the solar hydrogen production and organic pollution removal. However, pure g-C3N4 typically exhibits moderate photocatalytic activity. And the amorphous structures and the rapid recombination of the electron-hole pairs are the two main challenges for the improved photocatalytic performance of the single bulk g-C3N4. In this work, we reported the CoP as a co-catalyst modified high-crystalline g-C3N4 (HCCN) to form an stable and highly efficient CoP/HCCN composite via a simple solvothermal method. As expected, the as-prepared composites showed impressive photocatalytic performance toward the tetracycline (TC) degradation. In particular, 5 wt% CoP/HCCN exhibited the optimum photocatalytic efficiency (96.7%, 120 min) and its corresponding degradation rate constant is 10.2 times than HCCN. Additionally, the role of coexisting ions in simulated practical TC wastewater was explored. The enhanced photocatalytic performance mainly derives from two factors: (i) the formation of HCCN to reduce structural defects; (ii) CoP as the cocatalyst on the HCCN surface to accelerate the separation of the photo-generated electrons-hole pairs and strengthen the surface photoreaction of the samples. Our work opens up a new window to the construction of highly effective HCCN-based composite photocatalysts for solar light-driven wastewater treatment.
The N-CoP/CeO2 performs impressive long-term stability for over 42 days@10 mA cm−2 and 21 days@400 mA cm−2. The outstanding catalytic activity and unprecedented long-term durability derived from the ...robust 3D configuration, the synergetic effect of heterogeneous interfaces, the fast electron transportation, and the optimized absorption/desorption of the oxygen and hydrogen intermediates.
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•The N-CoP/CeO2 is fabricated through hydrothermal and nitridation-phosphorization treatment.•N-CoP/CeO2 possesses excellent conductivity, highly exposed active sites, and fast electron transportation.•N-CoP/CeO2 exhibits remarkable durability at 10 mA cm−2 (>42 days) and 400 mA cm−2 (>21 days) toward water splitting.•The contributions of N-CoP/CeO2 interfaces are deeply analyzed by DFT calculations.
Developing high-efficiency, low-cost, and durable bifunctional electrocatalysts for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is greatly desirable and challenging. Herein, a highly active and durable nitrogen-doped CoP coupled CeO2 nanowire heterostructure (N-CoP/CeO2) electrocatalyst is prepared on carbon cloth. The resultant N-CoP/CeO2 exhibits superb catalytic activities for OER and HER, featuring low overpotentials of 215 and 74 mV at 10 mA cm−2 in 1.0 M KOH. The N-CoP/CeO2 assembled water electrolyzer has super stability, which needs relatively low cell voltages of 1.52 V@10 mA cm−2 over 42 days (≈95.9 % retention) and 1.80 V@400 mA cm−2 over 21 days (≈94.4 % retention), outperforming most reported cost-effective electrocatalysts. Theoretical calculations reveal that the metallic heterostructure interfaces of N-CoP/CeO2 possess a fast electron transfer pathway, optimized adsorption/desorption process of reactive intermediates, and reduced reaction energetic barriers, thus enhancing the electrocatalytic activity. Additionally, the robust three-dimensional configuration and the oxygen vacancies-rich CeO2 component in N-CoP/CeO2 are regarded as significant contributors to improving stability and promoting long-term durability.
COPII mediates Endoplasmic Reticulum to Golgi trafficking of thousands of cargoes. Five essential proteins assemble into a two-layer architecture, with the inner layer thought to regulate coat ...assembly and cargo recruitment, and the outer coat forming cages assumed to scaffold membrane curvature. Here we visualise the complete, membrane-assembled COPII coat by cryo-electron tomography and subtomogram averaging, revealing the full network of interactions within and between coat layers. We demonstrate the physiological importance of these interactions using genetic and biochemical approaches. Mutagenesis reveals that the inner coat alone can provide membrane remodelling function, with organisational input from the outer coat. These functional roles for the inner and outer coats significantly move away from the current paradigm, which posits membrane curvature derives primarily from the outer coat. We suggest these interactions collectively contribute to coat organisation and membrane curvature, providing a structural framework to understand regulatory mechanisms of COPII trafficking and secretion.
Modulating and constructing interface engineering is an efficient strategy to enhance catalytic activity for water splitting. Herein, a hybrid nanoarray structure of V‐CoP@a‐CeO2, where “a” ...represents amorphous, integrated into carbon cloth is fabricated for water splitting. The synergy effect between V and CeO2 can increase the electron density of Co atoms at active sites, further optimizing the Gibbs free energy of H* adsorption energy (ΔGH*). Besides, V‐CoP@a‐CeO2 possesses lower water adsorption/dissociation energies, enabling accelerated reaction kinetics in alkaline media. As expected, the V‐CoP@a‐CeO2 exhibits superior performance toward the hydrogen evolution reaction and the oxygen evolution reaction. More importantly, a two‐electrode electrolyzer combined with an electrocatalyst of V‐CoP@ a‐CeO2 only demands that voltages of electrolytic cell are 1.56 and 1.71 V to achieve the current densities of 10 and 100 mA cm−2, respectively. This work provides guidance for the design or optimization of materials for water electrolysis and beyond.
The hybrid nanoarray structure of V‐CoP@a‐CeO2 integrated into carbon cloth is explored and developed for enhancing electrocatalytic activity and robust durability toward the water splitting reaction. Such excellent catalytic activities are attributed to the outer factors, which are structural advantages of nanorod arrays, and inner factors, which are strong electronic interactions on the interface.
•An ECL immunosensor for AFB1 based on illuminant COP T4VTP6 and quencher Fc-CHO/Phe.•COP T4VTP6 acted as a nanoreactor to catalyze and protect the formation of PtNPs.•The in situ generated PtNPs ...served as coreaction accelerator.•ECL response increased with increasing AFB1 via competition quenching mechanism.•The proposed system provides a great application platform.
Herein, a competitive quenching electrochemiluminescence immunosensor towards aflatoxin B1 (AFB1) detection was constructed by in-situ forming platinum nanoparticles (PtNPs) on ECL emitter COP T4VTP6 and effective ECL signal quencher Fc-CHO/Phe. In this system, cationic covalent organic polymer COP T4VTP6 emitted stronger cathode ECL signal at 765 nm, it acted as an interesting nanoreactor to immobilize PtCl62− through electrostatic adsorption, and directly in situ catalyzed the redox reaction to produce PtNPs without adding any external reducing agent, where PtNPs not only served as the substrate for antibody immobilization, but also played the role of coreaction accelerator to catalyze the production of SO4−, significantly improving more stable ECL signal. Moreover, the Fc-CHO/Phe labeled BSA-AFB1 was used for competitive reaction. Based on the efficient sensing strategy, ECL signal increased accordingly and exhibited linear signal responses with increasing AFB1, which realized a detection limit of 4.56 fg/mL, providing a promising potential on food analysis.
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