CO2热泵技术在供暖系统中的应用研究

针对自然工质CO2跨临界循环存在高排气温度和温度滑移等特点,论证其在热泵热水系统方面应用的优势。开发一套CO2热泵供暖系统,对供暖系统的热负荷和供热能力进行计算,同时对系统中的制冷机组、换热器、阀件、通风系统及风道进行试验分析。实际运行结果表明,该系统性能稳定、运行可靠、各项测试精度达到要求。     

The assessment of solar photovoltaic in Poland: the photovoltaics potential,perspectives and development

Clean Technologies and Environmental Policy - The following article explains the current condition of the photovoltaics sector both in Poland and worldwide. Recently, a rapid development of solar...     

Interactions between reducing CO2 emissions, CO2 removal and solar radiation management

We use a simple carbon cycle-climate model to investigate the interactions between a selection of idealized scenarios of mitigated carbon dioxide emissions, carbon dioxide removal (CDR) and solar radiation management (SRM). Two CO(2) emissions trajectories differ by a 15-year delay in the start of mitigation activity. SRM is modelled as a reduction in incoming solar radiation that fully compensates the radiative forcing due to changes in atmospheric CO(2) concentration. Two CDR scenarios remove 300 PgC by afforestation (added to vegetation and soil) or 1000 PgC by bioenergy with carbon capture and storage (removed from system). Our results show that delaying the start of mitigation activity could be very costly in terms of the CDR activity needed later to limit atmospheric CO(2) concentration (and corresponding global warming) to a given level. Avoiding a 15-year delay in the start of mitigation activity is more effective at reducing atmospheric CO(2) concentrations than all but the maximum type of CDR interventions. The effects of applying SRM and CDR together are additive, and this shows most clearly for atmospheric CO(2) concentration. SRM causes a significant reduction in atmospheric CO(2) concentration due to increased carbon storage by the terrestrial biosphere, especially soils. However, SRM has to be maintained for many centuries to avoid rapid increases in temperature and corresponding increases in atmospheric CO(2) concentration due to loss of carbon from the land.     

Metal halide perovskite: a game-changer for photovoltaics and solar devices via a tandem design

Multi-junction tandem design has been proven to be an effective means to further improve the efficiency of solar cells. However, its share in the photovoltaics market at present is tiny, since the most efficient tandem device comprises III-V semiconductors, which entail the use of expensive fabrication processes. The advent of perovskite solar cells, which have revitalized the PV field with their unprecedented pace of development, promises to address this bottleneck. Perovskite materials could not only serve as the top subcell absorber for commercial solar cells including Si and copper indium gallium selenide, but could work efficiently as bottom subcells owing to highly tuneable bandgaps which extend down to the range of ~1.2 to 1.5 eV. The highest-efficiency perovskite tandem to date was achieved by pairing a perovskite top cell with a Si bottom cell in a four-terminal configuration, yielding 26.4%. This review gives an overview of recent progress on the main tandem structures, and describes the detailed design improvements that have resulted in new record efficiencies. Ultimately, commercialization of these tandem solar cells relies on the scalability of perovskite technology. We, therefore, highlight the development of large-scale tandems and approaches to produce perovskite modules. We also point out the critical aspects that will require further effort and provide guidelines for future developments. The potential obstacles that will hamper the commercialization of perovskite tandems, if not adequately addressed, namely device stability and toxicity, are then critically examined. Finally, the substantial opportunities that perovskite materials open up for other solar devices with a tandem configuration are mentioned, which are attracting increasing attention.     

Trends in the development of the application of CO2-Lasers in materials technology

The applications of CO₂-lasers in Materials Technology are presented Examples in the areas of laser cutting, laser welding, surface heat treatment with and without melting and alloying are discussed.     

Water-side reversible CO2 heat pump for residential application

This paper presents the energy assessment of a water/water R744 chiller/heat pump, working according to a transcritical cycle, used for winter heating, summer cooling and tap water production. The different functions (heating, cooling, hot water) are managed water side. The analysis of the R744 chiller/heat pump is based on an original simplified method, which is able to predict the energy performance of the unit based only on its performance data at the nominal rating conditions. The method was validated against experimental data. A comparison with a state-of-the-art R410A unit is presented. The monthly analysis shows that the CO₂ unit is very efficient in hot water production, but penalised in heating and cooling service. The adoption of an ejector in place of the expansion valve makes the CO₂ system reach the same energy consumption as the R410A unit, despite the presence of the water loop only in the R744 lay-out.     

Highly efficient nanostructured metal-decorated hybrid semiconductors for solar conversion of CO2 with almost complete CO selectivity

Photocatalytic reduction of CO₂ into solar fuels is regarded as a promising method to address global warming and energy crisis problems. Although heterostructured hybrid metal oxide catalysts have been used for CO₂ reduction, selective control for CO production-only remains the subject of debate. In this paper, we report an absolute selectivity for CO production-only with enhanced photocatalytic ability using Ag-decorated reduced titanium oxide/tungsten hybrid nanoparticles (blue TiO₂/WO₃–Ag HNPs) at 1166.72 μmol g⁻¹ h⁻¹ with an apparent quantum yield of 34.8%. The construction of a Z-scheme between blue TiO₂ and WO₃ domains with an excellent band alignment provided remarkably improved separation of photoinduced charges. Importantly, the presence of novel Ag not only produces the highest selectivity up to 100% CO production-only, but also increases the photocatalytic electron reaction rate (2333.44 μmol g⁻¹ h⁻¹).     

Growth of PbS nanopyramidal particulate films for potential applications in quantum-dot photovoltaics and nanoantennas

We report a simple interfacial process called the liquid-liquid interface reaction technique (LLIRT) that leads to the formation of nanosized PbS particulate films with hitherto unreported pyramidal morphology. The resultant PbS films were characterized by transmission electron microscopy (TEM) with selected area electron diffraction (SAED), X-ray diffractometery (XRD), atomic force microscopy (AFM), near field scanning optical microscopy (NSOM) and UV-vis spectroscopy. The pyramidal morphology is speculated to originate from the preferred orientation of the 2 2 0 plane of cubic PbS. Our nanopyramidal PbS particulate films display remarkably sharp excitonic peak centered around 656 nm that accounts for a band gap of 1.8 eV suggesting, in turn, their potential application in QD photovoltaics. Interestingly, the feasibility of such nanopyramids to potentially act as nanoantennas (as revealed by the NSOM) is also suggested.     

Photocatalyzing CO2 to CO for Enhanced Cancer Therapy

Continuous exposure to carbon monoxide (CO) can sensitize cancer cells to chemotherapy while protect normal cells from apoptosis. The Janus face of CO thus provides an ideal strategy for cancer therapy. Here, a photocatalytic nanomaterial (HisAgCCN) is introduced to transform endogenous CO₂ to CO for improving cancer therapy in vivo. The CO production rate of HisAgCCN reaches to 65 µmol h^?1 g_mat^?1, which can significantly increase the cytotoxicity of anticancer drug (doxorubicin, DOX) by 70%. Interestingly, this study finds that HisAgCCN can enhance mitochondria biogenesis and aggravate oxidative stress in cancer cells, whereas protect normal cells from chemotherapy‐induced apoptosis as well. Proteomics and metabolomics studies reveal that HisAgCCN can enhance mitochondria biogenesis and aggravate oxidative stress in cancer cells specifically. In vivo studies indicate that HisAgCCN/DOX combination therapy presents a synergetic tumor inhibition, which might provide a new direction for clinical cancer therapy.     

Solvothermal synthesis of CuInS2 powders and CuInS2 thin films for solar cell application

In this study, a facile solvothermal method was developed to prepare CuInS₂ powders and CuInS₂ thin films. The CuInS₂ powders and CuInS₂ thin films were prepared by solvothermal route using the precursor of Copper (II) chloride, indium (III) nitrate, thiourea, oxalic acid, hexadecyl trimethyl ammonium bromide and ethanol. The morphology, crystallographic structure, chemical composition and optical band gap of CuInS₂ powders and CuInS₂ thin films were investigated using scanning electronic microscope (SEM), X-ray diffraction (XRD), energy dispersive spectrometry (EDS) and UV–vis spectroscopy. The results reveal that both CuInS₂ powders and CuInS₂ thin films are in chalcopyrite phase. The CuInS₂ powders are mainly composed of flower-like microspheres. Both microstructure of the sphere surface and diameter of sphere are affected by indium nitrate concentration in precursors. The CuInS₂ thin films are composed of a large number of uniform flower-like nanosheets, and the nanosheets become smaller in size and denser in distribution density with increasing concentration of thiourea. The optical band gap is found to be 1.44 and 1.52 eV for CuInS₂ powders and CuInS₂ thin films, respectively. The deposition mechanism of the CuInS₂ is discussed.     

太阳能集热板镀膜及其设备

介绍了采用真空磁控溅射的方法在太阳能集热板上镀选择性吸收膜，从而使平板太阳能热水器的热效率得到提高；集热板的αs=0．91～0．96；ε≤0．1。并介绍了镀膜设备的性能。     

隔板蒸馏塔技术及其在空气分离中的潜在应用

隔板蒸馏塔是完全热耦合蒸馏,具有节能、投资低的优点。文章介绍了隔板蒸馏塔的原理、结构及设计方法,并指出了它在空气分离中的潜在应用。     

筒式粘弹性阻尼器的试验研究及工程应用

在不同环境温度、激励频率和应变幅值下,对筒式粘弹性阻尼器的动力性能指标进行了试验研究,研究表明筒式粘弹性阻尼器具有较为稳定的动力性能,耗能能力强。往复振动下阻尼器因内升温引起粘弹性材料软化,动力性能指标变化较大,设计中应考虑荷载循环次数的影响。本文通过试验研究了滞回圈数对筒式粘弹性阻尼器动态力学性能的影响,并据此提出了设计建议。本文还介绍了筒式粘弹性阻尼器的老化性能试验和疲劳性能试验,试验结果表明具有良好的老化性能,在风振或地震下阻尼器具有较好的耐疲劳性能。最后介绍了筒式粘弹性阻尼器风振控制的工程应用实例,计算表明结构悬挑端竖向位移和加速度明显减小。     

Exploration of CO2 emission reduction pathways: identification of influencing factors of CO2 emission and CO2 emission reduction potential of power industry

Clean Technologies and Environmental Policy - Low-carbon development of China's power sector is the key to achieving carbon peaking and carbon neutrality goals. Based on the logarithmic mean...     

Glow-discharge-produced amorphous semiconductors and their application to solar coatings

Recent developments in the physics and technology of tetrahedrally bonded amorphous semiconductors are reviewed. First, some unique advantages of these materials are discussed from the point of view of their basic physical properties and of their technological applications. The current state of the art in the development and technology of amorphous silicon solar cells is surveyed, and some new approaches and key technologies which enable efficiencies of the order of 10% to be attained are introduced. The principle advantages of photothermal conversion in p-type hydrogenated amorphous siliicon films are described. Some fundamental properties of photothermal conversion using this material are presented. Finally, a newly developed amorphous silicon photovoltaic-photothermal hybrid solar coating device with a conversion efficiency in excess of 55% is described.     

Advanced damage-free neutral beam etching technology to texture Si wafer with honeycomb pattern for broadband light trapping in photovoltaics

Journal of Materials Science: Materials in Electronics - We introduce a new innovative damage-free neutral beam etching (NBE) technique to transfer a honeycomb resist pattern to silicon (Si) wafer...     

Recovering CO2 and N2 from combustion exhaust gas use membrane technology

Enerfex, Inc. is a start-up company actively involved in various process development and design activities. Most of Enerfex's processes involve gas separation membranes. Enerfex holds the patent on the Cryocogen process and apparatus that allows the application of membranes to combustion exhaust gas. Cryocogen technology is the application of gas separation membranes to combustion exhaust gas to simultaneously produce high purity carbon dioxide and nitrogen. The system is described here.