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A novel cycle model of the capacitive salinity/heat engine mainly consisting of nano-porous super-capacitors is established for harvesting mixed free energy caused by salinity difference between the river water and the seawater, and the thermal energy due to the temperature difference. The heat engine is charged and discharged in the cycle of a low temperature brine and a high temperature fresh water, respectively. The analytical expressions of the cyclic work output and efficiency are given. General performance characteristics of the capacitive salinity/heat engine are analyzed. The temperature of the heat reservoir and salt concentration of seawater are optimized to improve the efficiency of the capacitive salinity/heat engine. The optimal selection ranges of several main parameters are provided. When the Stern distance is equal to 1 nm and the charging voltage is equal to 3.5V, the energy conversion efficiency of the capacitive salinity/heat engine is about 40%, while the pure thermal efficiency in the cycle is about 16.9%. The energy conversion efficiency of the capacitive salinity/heat engine is significantly larger than that of the capacitive heat engine. The results obtained can facilitate the application of this technology to real life, which can reduce the consumption of fossil fuels.

Energy harvesting from sun and outer space using thermoradiative devices (TRDs), despite being promising renewable energy sources, is limited only to daytime and nighttime period, respectively. Such a system with 24-hour continuous electric power generation remains an open question thus far. Here, a TRD-based power generator that harvests solar energy via concentrated solar irradiation during daytime and via thermal infrared emission towards the outer space at nighttime is proposed, thus achieving the much sought-after 24-hour electrical power generation. Correspondingly, a rigorous thermodynamical model is developed to investigate the all-day performance characteristics, parametric optimum design, and the role of various energy loss mechanisms. The calculated results predict that the daytime TRD-based system yields a peak efficiency of 12.6% under 10 suns, thus significantly outperforming the state-of-art record-setting solar thermoelectric generator. This work reveals the potential of TRD towards 24-hour electricity generation and future renewable energy technology.

The production of redundant waste heat limits the performance of photovoltaic cells, so removing waste heat and converting it back into electricity is a promising way to improve the utilization of solar energy. A new concentrated solar spectrum photovoltaic-thermophotovoltaic hybrid system mainly is proposed. Full-spectrum solar energy is split into different parts according to specific requirements. Expressions for the efficiency and power output of the system are derived. The effects of the voltage output and area ratio of the two subsystems, the bandgap energy of semiconductor in the photovoltaic cell, and the solar concentration factor on the system performance are analyzed comprehensively. By optimizing several key parameters, the problem of the optimal matching between two subsystems is solved. The performance characteristics of the system are revealed, and the maximum efficiency and corresponding power output density of the hybrid system are calculated numerically, reaching 47.74% and 31.13W cm−2, respectively, which are 9.190% and 19.25% higher than those of a single photovoltaic cell. The optimal selection criteria of several key parameters are provided. By comparison with other PV-based systems, the proposed system not only maintains a high energy conversion efficiency but also produces a relatively larger power output density.

A neoteric model of the solar-driven integrated device mainly composed of a thermionic generator (TIG) with a graphene-based anode and a thermophotovoltaic cell is presented, where the major irreversible losses inside and outside the system are considered. The analytical expressions for the power output and efficiency of two subsystems and the integrated device are derived. The temperatures of the emitter and collector are determined through heat balance equations. The effects of the voltage outputs of the generator and cell, area ratio of the absorber to the emitter, bandgap energy of the cell, and solar concentration factor on the systemic performance are evaluated. Several main parameters are optimized and parametric selection criteria are provided. The maximum efficiencies of the integrated device operated at different conditions are calculated. For example, under 1000 solar concentration, the efficiency of the integrated device attains 45.23%, which is obviously higher than that of a single solar-driven TIG (STIG) or other existing hybrid systems with a traditional TIG. It is found that replacing metallic anode by graphene anode and integrating a photovoltaic cell into the STIG largely enhance the conversion efficiency of solar energy.

From the experimental data of the isofield heat capacity of the MnFe-based magnetocaloric materials, magnetic entropy change versus temperature characteristic curves are obtained by using numerical value calculation procedure. Three kinds of MnFe-based magnetocaloric materials, in which there are all a large magnetocaloric effect, are selected as the constituent materials to establish a novel composite magnetocaloric material, for which keeping large magnetic entropy change over a wide temperature range is desired. By means of thermodynamic analysis and optimal control theory, the molar mass ratios of each constituent material to the composite material are optimally determined for differently applied magnetic fields. The optimum results show that when the applied magnetic field μ0H″=2 T, the optimum molar mass ratios x1opt, x2opt, and x3opt of Mn1.24Fe0.76P0.75Ge0.25, Mn1.2Fe0.8P0.75Ge0.25, and Mn1.1Fe0.9P0.78Ge0.22 to the composite are equal to 0.44, 0.11, and 0.45, respectively. Furthermore, the regenerative Ericsson refrigeration cycle employing the composite or constituent materials as the working substance is set up. The effects of the non-perfect regeneration on the net cooling quantity, COP, etc. of the refrigeration cycle are analyzed and evaluated. The cycle performances of the composite material are compared with those of the constituent materials. It shows that the net cooling quantity and COP of the composite are much larger than those of any constituent material. The numerical calculation results obtained can provide some reference for the selection of working substances and the optimal parameter design of room temperature magnetic refrigerators.

Cancer therapeutics are varied and target diverse processes in cancer progression. Photodynamic therapy (PDT), photothermal therapy (PTT), and the inhibition of pro-cancer proteases are non-invasive anticancer therapeutics that attract increasing attentions for their enhanced specificities and milder systemic toxicities compared to traditional therapeutics. These modalities offer advantages to compensate for the shortcomings of their counterparts. For instance, PDT or PTT efficiently eliminates locally confined tumor cells while exhibiting no effect on metastatic tumor cells. In contrast, the inhibition of pro-cancer proteases systemically suppresses the proliferation and metastasis of cancer cells but does not eradicate existing cancer cells. To synergize these therapeutics, we hereby report a versatile nanoparticle that integrates the effects of PDT, PTT, and enzyme-inhibition. This nanoparticle (CIKP-NP) was synthesized by covalently or non-covalently modifying a photothermal nanoparticle with a photosensitizer, a pro-cancer protease inhibitor, and an albumin-binding molecule. After confirming the PDT, PTT, albumin-binding, and enzyme-inhibition properties at the molecular level, we demonstrated that CIKP-NP killed tumor cells through PDT or PTT and suppressed tumor cell invasion through enzyme-inhibition. In addition, through a breast cancer xenograft mouse model, we demonstrated that CIKP-NP suppressed tumor growth by PDT or PTT effect. Notably, the synergism of PDT and PTT significantly enhanced its anticancer efficiency. Furthermore, CIKP-NP significantly suppressed cancer metastasis in a lung metastatic mouse model. Last, biodistribution and the in vivo retention of CIKP-NP confirmed the tumor-targeting property. Beyond demonstrating the anti-tumor and anti-metastatic efficacy of CIKP-NP, our study also suggests a new strategy to synergize multiple anticancer therapeutics.

An irreversible model of the thermophotonic cell (TPC) with a heated forward-based light-emitting diode (LED) as an emitter and a photovoltaic cell (PVC) is established. The performances of the TPC are optimized and compared with those of the thermophotovoltaic cell (TPVC) based on finite-time thermodynamics. The results obtained show that there exist the optimally operating ranges of the voltages and band-gap energies of the LED and PVC. The thermal flow emitted from the heated LED dramatically exceeds that from the pure thermal emitter. The maximum efficiency of the TPC is less than that of the TPVC, whereas the maximum power density of the TPC surpasses that of the TPVC under an arbitrary emitter temperature. The TPC has the advantages of the relatively high optimal band-gap energies and relatively low-operating temperatures so that it is easier to be made than the TPVC.

Targeted therapy showed broad application prospects in the treatment of various types of cancer. Through carriers such as aptamers, antibodies, proteins and peptides, targeted therapy can selectively deliver drugs into tumor cells. Compared with traditional treatment methods such as chemo- and radiotherapy, targeted drug delivery systems can reduce the toxic effects of drugs on normal cells and avoid adverse reactions. Herein, an aptamer-cyclometalated iridium(III) complex conjugate (ApIrC) has been designed and developed as a targeted anticancer agent. Owing to the targeting ability of aptamers, ApIrC specifically bound to nucleolin over-expressed on the surface of cancer cells and showed strong fluorescence signal for tumor imaging and diagnosis. ApIrC had more substantial cellular uptake in cancer cells than the iridium complex alone and exhibited favorable low toxicity to normal cells. After uptake by cells through endocytosis, ApIrC can selectively accumulated in mitochondria and induced caspase-3/7-dependent cell death. Remarkably, ApIrC can also specifically target 3D multicellular spheroids (MCSs) and show excellent tumor permeability. So, it can effectively reach the interior of MCSs and cause cell damage. To our knowledge, this is the first report of the aptamer-cyclometalated iridium(III) complex conjugate which studied for cancer targeted therapy. The developed conjugate has great potential to be developed as novel therapeutics for effective and low-toxic cancer treatment.

Combined cooling, heating, and power (CCHP) is an economic and eco-friendly technology to mitigate energy issues with remarkable energy efficiency improvement. This study formulates a mixed integer nonlinear programming (MINLP) model for a combined CCHP system coupled with renewable energy, i.e. RCCHP system, which is applied in five different buildings to evaluate the economic and environmental performance under two optimization modes. Net present value (NPV), internal rate of return (IRR) and dynamic payback period (DPP) are introduced as economic indexes, while CO2 emission reduction rate (CER) is considered as the environmental indicator to determine the optimal combination, capacity, and operation strategies for energy technologies. Results indicate that a combination of electricity purchased at valley period during night with power generated by the combined heating and power (CHP) unit coupled with wind turbine in peak period during daytime is cost-optimal which also enables higher energy efficiency. Meanwhile, the feed-in tariff as well as the uncoordinated electrical and thermal loads both show a significant impact on real-time operation strategies. Compared with the reference separate production (SP) system, the combined system shows better performance when applied to shopping mall under both optimization modes, e.g., with NPV up to 67.65 and 46.61 million RMB, IRR up to 20.70% and 25.10%, and the minimum DPP is 5.49 and 4.82 years under NPV and IRR maximization, respectively.

A novel model of the coupling system consisting of a solar collector and an alkali metal thermal electric converter (AMTEC) is proposed, in which various irreversible losses are considered. Analytical expressions for the efficiencies of the solar collector, AMTEC, and coupling system are derived. The operative temperatures of the solar collector and AMETC are determined by energy balance equations rather than some specified parameters. The influences of the thickness of the electrolyte membrane, current density, and area ratio of the absorber to the AMTEC on the performance of the system are discussed. The maximum efficiency and power output density for a given value of the solar concentration ratio are calculated and revealed to be two different operation states of the coupling system. The effects of the solar concentration ratio on the optimal regions of some key parameters are discussed in detail. The optimum selection criteria of these parameters are provided.

Antimicrobial photodynamic therapy (aPDT) is a new therapeutical modality highly advocated recently to meet the challenge of drug resistant bacteria. In this study, we developed a composite material to combine silver nanoparticle, a commonly used disinfectant, with a potent photosensitizer for aPDT. Interestingly, we found the photosensitizer activated the silver nanoparticles into silver ions under light illumination. At the same time, silver nanoparticles enhanced the generation of ROS by the photosensitizer. Together, the two components activates each other, leading to remarkable antimicrobial efficacy against not only gram-positive and -negative bacteria, but also drug resistant bacteria (Methicillin Resistant S. aureus, MRSA). Such antimicrobial effect was further demonstrated on a bacterial infection model on mice. We showed that the chemical treatment, the high temperature or the pressure during the preparation did not affect the cellulosic structures of the fabric based on the characterization of optical, mechanical and thermal properties of the composite material. aPDT is typically a localized therapy, depending on the contact of bacteria to the photosensitizers, while the silver nanoparticles released the silver ions into the solution and can kill the bacteria thereof. Thus, our current study demonstrates the complementarity of aPDT and silver nanoparticles and mutual promotion of antibacterial effects to even drug-resistant bacteria.

The aim of this study is to deeply search the performance of the coupling system comprised of a direct carbon fuel cell and an alkali metal thermal electric converter. The main contents of this study are to propose the model of the novel coupling system by considering the main irreversible losses, derive the efficiency and power output of the whole system, discuss the influences of the electric current of the fuel cell, the electrolyte thickness, and the ratio of the electrode areas of two subsystems on the systemic performances, and, evaluate and compare the performances of the whole system and the fuel cell. The main novelties are to provide parametric optimum choice criteria and give the reasonably matching schemes of two subsystems. The results obtained reveal the advantages of the present coupling system.

Background Photodynamic therapy (PDT), a clinical anticancer therapeutic modality, has a long history in clinical cancer treatments since the 1970s. However, PDT has not been widely used largely because of metabolic problems and off-target phototoxicities of the current clinical photosensitizers. Purpose The objective of the study is to develop a high-efficiency and high-specificity carrier to precisely deliver photosensitizers to tumor sites, aiming at addressing metabolic problems, as well as the systemic damages current clinical photosensitizers are known to cause. Methods We synthesized a polydopamine (PDA)-based carrier with the modification of folic acid (FA), which is to target the overexpressed folate receptors on tumor surfaces. We used this carrier to load a cationic phthalocyanine-type photosensitizer (Pc) and generated a PDA-FA-Pc nanomedicine. We determined the antitumor effects and the specificity to tumor cell lines in vitro. In addition, we established human cancer-xenografted mice models to evaluate the tumor-targeting property and anticancer efficacies in vivo. Results Our PDA-FA-Pc nanomedicine demonstrated a high stability in normal physiological conditions, however, could specifically release photosensitizers in acidic conditions, eg, tumor microenvironment and lysosomes in cancer cells. Additionally, PDA-FA-Pc nanomedicine demonstrated a much higher cellular uptake and phototoxicity in cancer cell lines than in healthy cell lines. Moreover, the in vivo imaging data indicated excellent tumor-targeting properties of PDA-FA-Pc nanomedicine in human cancer-xenografted mice. Lastly, PDA-FA-Pc nanomedicine was found to significantly suppress tumor growth within two human cancer-xenografted mice models. Conclusion Our current study not only demonstrates PDA-FA-Pc nanomedicine as a highly potent and specific anticancer agent, but also suggests a strategy to address the metabolic and specificity problems of clinical photosensitizers.

Without fabricating intermediate tunnel junctions or wafer bonding schemes for interconnecting the subcells, heterojunction bipolar transistor solar cells offer a promising new route in solar energy conversion. In this work, an improved theory for the three-terminal heterojunction bipolar transistor solar cell is presented with inclusion of non-ideal effects missing from the previous treatment, namely the non-radiative recombination and the thermal conduction losses that are inevitably present in realistic devices. Following detailed balance theory, the revised analytical formula for the cell conversion efficiency is derived, and the maximum efficiencies under different conditions are further calculated. Under the condition of 100 sun irradiance and 50% injection efficiency, a Gallium arsenide/Gallium antimonide-based solar cell operating at 465 K yields a maximum efficiency of 46.4%. Moreover, the effects of solar concentration, injection efficiency, and other key parameters on the cell performance are analyzed, and, consequently, optimal operating conditions and limiting factors on the conversion efficiency are determined. Simulation results show that such a solar cell operating with low injection efficiency under moderate concentration factor and low cell temperature can significantly boost its conversion performance. This work provides new physical insights for optimal designs, thus paving a route towards the development of low-cost high-performance solar cells.

Fuel cell-gas turbine hybrid system is a potential field of investigation. This study establishes a modeling and optimization framework for a novel hybrid system consisting of a solid oxide fuel cell, a gas turbine and a supercritical carbon dioxide Brayton cycle. Based on the proposed thermodynamical model, a parametric analysis is investigated to determine the impacts of several key parameters on the system exergoeconomic performance. Meanwhile, bi-objective optimization is conducted for maximizing the exergy efficiency and minimizing the levelized cost of electricity via the Epsilon-constraint approach. The Linear Programming Techniques for Multidimensional Analysis of Preference decision-making approach is further employed to select the Pareto optimum solution from Pareto frontiers. The results show that several extreme values for the exergy efficiency and the levelized cost of electricity exist in a series of sensitivity curves, respectively. The Pareto frontiers indicates that with the increase of the exergy efficiency, the levelized cost of electricity shows a moderately increasing trend at first and increases rapidly afterward. Overall, at the Pareto optimum solution, the combined system can achieve an optimal exergy efficiency and levelized cost of electricity by 68% and 0.0575 $ kWh−1, respectively.

Thioredoxin reductase (TrxR), a major component of the thioredoxin system, makes a critical role in regulating cellular redox signaling and is found to be overexpressed in many human cancer cells. TrxR has become an attractive target for anticancer agents. In this work, three Ru(II) complexes with salicylate as ligand, [Ru(phen)2(SA)] (phen = 1,10-phenanthroline, SA = salicylate, 1), [Ru(dmb)2(SA)] (dmb = 4,4′-dimethyl-2,2′-bipyridine, 2) and [Ru(bpy)2(SA)] (bpy = 2,2′-bipyridine, 3), were synthesized and characterized. The anticancer effect exerted by them was evaluated. Complex 1 was found to exhibit obvious anticancer activity, in comparison with cisplatin, against cancer cell lines, while displaying low toxicity to the normal cell line BEAS-2B. The mechanism of complex 1 cancer cell growth suppress was investigated in A549 cells. Complex 1 exerted its anticancer through inducing apoptosis and triggering cell cycle arrest at the G0/G1 phase. Complex 1 can selectively inhibit TrxR activity and thus promote the generation and accumulation of reactive oxygen species (ROS), which subsequently trigger mitochondrial dysfunction and DNA damage, activate oxidative stress-sensitive mitogen activated protein kinase (MAPK), and suppress the protein kinase B (PKB or AKT) signal pathway, resulting in apoptosis in A549 cells.

A novel Stirling-like irreversible electrochemical thermo-capacitive regenerative cycle operating between a heat reservoir and a heat sink for harvesting low-grade heat is proposed, in which the main irreversible losses are considered. Expressions for the efficiency and power output of the cycle are derived. The inherent regenerative heat loss of the cycle is revealed. The influences of several important parameters, such as the capacitance of the supercapacitor, charge ratio, endpoint voltage of the charging process on the power output of the cycle are discussed. The maximum power output and corresponding efficiency are calculated. The results show that when the charging endpoint voltage of the electrochemical thermo-capacitive regenerative cycle is 10 V, the maximum power output is 31.9 W and the efficiency at the maximum power output can reach 12.8%, which is 51.2% of the Carnot efficiency. The optimal values for several parameters at the maximum power output are determined. The parametric optimum selection criteria of the cycle are provided. The results obtained can ensure the cycle to operate in the optimum states.

Two new cyclometalated Ru(II)-β-carboline complexes, [Ru(dmb)2(Cl-Ph-βC)](PF6) (dmb = 4,4′-dimethyl-2,2′-bipyridine; Cl-Ph-βC = Cl-phenyl-9H-pyrido[3,4-b]indole; RuβC-3) and [Ru(bpy)2(Cl-Ph-βC)](PF6) (bpy = 2,2′-bipyridine; RuβC-4) were synthesized and characterized. The Ru(II) complexes display high cytotoxicity against HeLa cells, the stabilized human cervical cancer cell, with IC50 values of 3.2 ± 0.4 μM (RuβC-3) and 4.1 ± 0.6 μM (RuβC-4), which were considerably lower than that of non-cyclometalated Ru(II)-β-carboline complex [Ru(bpy)2(1-Py-βC)] (PF6)2 (61.2 ± 3.9 μM) by 19- and 15-folds, respectively. The mechanism studies indicated that both Ru(II) complexes could significantly inhibit HeLa cell migration and invasion, and effectively induce G0/G1 cell cycle arrest. The new Ru(II) complexes could also trigger apoptosis through activating caspase-3 and poly (ADP-ribose) polymerase (PARP), increasing the Bax/Bcl-2 ratio, enhancing reactive oxygen species (ROS) generation, decreasing mitochondrial membrane potential (MMP), and inducing cytochrome c release from mitochondria. Further research revealed that RuβC-3 could deactivate the ERK/Akt signaling pathway thus inhibiting HeLa cell invasion and migration, and inducing apoptosis. In addition, RuβC-3-induced apoptosis in HeLa cells was closely associated with the increase of intracellular ROS levels, which may act as upstream factors to regulate ERK and Akt pathways. More importantly, RuβC-3 exhibited low toxicity on both normal BEAS-2B cells in vitro and zebrafish embryos in vivo. Consequently, the developed Ru(II) complexes have great potential on developing novel low-toxic anticancer drugs.

The aim of this study is to deeply search and understand the performance of the coupling system composed of an alkali metal thermoelectric converter and a thermoelectric generator. The main methods are to update the model of the coupling system, which includes the main irreversible losses existing in subsystems and coupling system, and obtain the analytical expressions of the power outputs and efficiencies of two subsystems and coupling system. The main novelties are to discuss the influences of the thickness of the β ″ -alumina solid electrolyte on the whole performance of the system and solve the matching problem between two subsystems. The main contents of this study include that the influences of the thickness of the electrolyte membrane, current density of the alkali metal thermoelectric converter, and electric current of the thermoelectric generator on the power output density and efficiency are discussed and the maximum power output density and efficiency of the system are calculated and compared with those of the single alkali metal thermoelectric converter and the existing coupling models. The results obtained reveal the advantages of the present model. The whole performance of the coupling system can be optimized and the parametric selection criteria of several key parameters of the coupling system operating at optimum states can be provided, When the thickness of the electrolyte membrane is optimally selected, the maximum efficiency of the present model attain 34.6% and increase about 10.4%, compared with those of the existing best coupling system. The waste heat released by the alkali metal thermoelectric converter can be efficiently utilized by the thermoelectric generator.

A new model of the intermediate band thermoradiative cell (IBTRC) is put forward. Expressions for the power output density (POD) and efficiency of the IBTRC are derived. The current densities and PODs arising from the normal transitions and interband transitions of electrons are compared. It is found that when the IBTRC with a bandgap of 0.2 eV is operated between the heat source at 1000 K and the surroundings at 300 K, the maximum POD and efficiency of the cell are approximately $1.583\times $ and $1.096\times $ of those of the thermoradiative cell without intermediate bands (IBs) under the same operating temperature and bandgap, respectively. This shows that the performance of the IBTRC can be largely improved by the insert of the IB. Moreover, the optimal selection criteria of some key parameters are provided, and then the optimum operating conditions of the IBTRC are determined. Finally, several issues that will influence the performances of the IBTRC are pointed out. These results may help engineers to fabricate high-performance IBTRCs.

Antimicrobial photodynamic therapy (aPDT) is an effective way to combat infectious diseases and antibiotic resistance. Photosensitizer is a key factor of aPDT and has triggered extensive research interest. In this study, a new asymmetric Zn(II) phthalocyanine mono-substituted with a triazatricyclodecane moiety (compound 3 ) and its cationic N -methylated derivative (compound 4 ) were synthesized. Their photodynamic antimicrobial activities were evaluated using bioluminescent bacterial strains. Compound 3 showed phototoxicity only toward the Gram-positive bacteria, whereas the cationic derivative compound 4 exhibited strong anti-bacterial activity against both Gram-positive and Gram-negative strains. These bacterial species were eradicated (>4.0 logs or 99.99% killing) at appropriate concentrations of compound 4 with 12.7 J/cm 2 of red light, demonstrating compound 4 as a potent aPDT agent.

An updated model of the solar spectrum splitting photovoltaic cell-thermoelectric generator system is used to derive the analytical expression of the systemic efficiency. The cutoff energy of the system, cell voltage, and dimensionless current of the thermoelectric generator are optimized. Particularly, the influences of the area ratio of the collector to photovoltaic cell on the performance of the spectrum splitting system are discussed in detail. The maximum efficiencies of the spectrum splitting system are calculated for given solar concentration factors. The results obtained are compared with those of the single photovoltaic cell with the same solar concentration factor. It is found that the maximum efficiency of the system can be further improved when the area ratio is optimized. The expressions of the upper and lower bounds of the optimized area ratio are derived. The spectrum splitting system can more efficiently harvest the full solar spectrum than the single photovoltaic cell, especially at low solar concentration factors. For example, when solar concentration factors are, respectively, equal to 30 and 100, the maximum efficiencies of the spectrum splitting system attain 39.5% and 40.2% and increase approximately 2.67% and 2.19%, compared to those of the single photovoltaic cell.

A coupling system composed of a high temperature fuel cell such as a molten carbonate fuel cell (MCFC), a regenerator, and a thermoradiative cell (TRC) is established. The efficiency and power output of the coupling system are analytically derived. The performances of the system are evaluated. The optimum operation states of the system are determined. The optimal selection criteria of some key parameters are provided. It is found that when the MCFC is operated at the temperature of 923 K and the band gap of the TRC equals 0.2 eV, the maximum power output density (MPOD) of the coupling system is approximately 2.020 times of that of a single MCFC and the corresponding efficiency of the coupling system is approximately 1.304 times of that of the MCFC. The percentage improvements of the MPODs of the coupling system and other MCFC-based coupling systems in the existing literatures are compared. The results show that the MCFC-TRC coupling system can exhibit better performance and make use of the waste heat released by the MCFC more effectively in comparison with other MCFC-based coupling systems. Moreover, it is expounded that the TRC is an efficient device which can recycle and utilize the waste heat produced by other high temperature fuel cells such as solid oxide fuel cells and direct carbon fuel cells.

Plasma-derived human serum albumin (pHSA) has important applications in many clinical indications, including blood loss, serious burn, or hemorrhagic shock. The limited supply and potential infectious pathogen contamination of pHSA have stimulated the development of recombinant human serum albumin (rHSA). However, rHSA often entraps endogenous or exogenous impurities, including color pigments and polysaccharides. Therefore, the purification of rHSA to high purity remains the bottleneck in large-scale production of rHSA. Herein we report a novel two-step purification protocol for rHSA generated from Pichia pastoris. In the first step, rHSA was partially unfolded to expose impurities entrapped into rHSA and was then removed. In the second step, rHSA was crystallized to further remove impurities. Through this procedure, the pigment content (A350/A280) and polysaccharides content of rHSA were reduced to 0.0141 and 0.253 μg/mg, respectively, which were comparable to pHSA. In addition, the secondary structure and bioactivity of purified rHSA are preserved. The purification procedure developed in this study is a simple, short and low cost method to produce active rHSA, or rHSA-fusion proteins, to high purity, and also suitable for the purification of other disulfide-rich proteins.

A thermionic-thermoradiative converter (TITRC) is established by combining the concepts of the thermionic emission and thermoluminescence, where the main irreversible losses are considered. The TITRC utilizes simultaneously electron and photon fluxes and converts directly a part of them into electricity, which enables a significant enhancement on the heat transfer and performance of the TITRC. Compared with either the thermionic energy generator or the thermoradiative device, the TITRC possesses advantages of higher power output and conversion efficiency in an extended temperature range. When the emitter in the TITRC is operated at 1500 K and Ag-O-Cs is used as the collector, the maximum power density and efficiency of the proposed TITRC can reach up to 0.301 Wcm $^{-2}$ and 22.5%, respectively. This letter can benefit the optimal design of the TITRC, and shed light on developing the ongoing research of the alternative energy harvesting devices.

Antimicrobial photodynamic therapy (aPDT) is an effective mean for killing bacteria in this era of increasing multi-antibiotic resistance, and possesses a number of unique advantages. Much effort has been devoted to the development a key component of aPDT photosensitizers (PSs). We synthesized a series of PSs with different positive charges (ZnPc(Lys)[Formula: see text], where [Formula: see text] 3, 5, 7, and studied their antibacterial activities and mechanisms against Escherichia coli (E. coli). Interestingly, the ZnPc(Lys)[Formula: see text] derivative showed stronger antibacterial effect (MIC = 25.3 [Formula: see text]M) than the other two PSs (MICs = 50.6 [Formula: see text]M), even though this PS did not have the highest uptake on bacteria among these PSs. It was ZnPc(Lys)[Formula: see text] that possessed the highest bacterial uptake. ZnPc(Lys)[Formula: see text] was found to have the highest monomeric fractions (62.0%) on bacteria surface than the other two PSs (37.9% for [Formula: see text] 3 and 33.9% [Formula: see text] = 7). These results clearly demonstrate that PS conformation on bacterial surface as a key parameter determining antibacterial efficacy of PSs. Other mechanistic aspects of photodynamic effects, including PS binding kinetics, bacterial surface hydrophobicity, zeta potential of bacteria, membrane permeability and bacterial signaling pathways were also studied.

Quantum-size effects unavoidably produce imperfect-regeneration heat losses in irreversible isothermal expansion/compression cycles, leading to the less efficiency of micro engines. Here, we design a smallest quantum Stirling-like heat engine using a single trapped electron as the working substance. The quantum probabilities to determine the electronic position are constructed from the incoherent mixed ensemble. When the quantum well expands isothermally to double its size and an infinite delta-function potential barrier is inserted in the middle, the complete degeneracies enable the heat engine to work reversibly and achieve the Carnot efficiency. The proposed theoretical model can open up new avenues for building practical nano-energy devices.

The cycle model of an alkali metal thermal electric converter (AMTEC) is updated, where the relation between the thickness of the electrolyte and the other parameters of the AMTEC is established. The effects of thickness of the electrolyte on the performance of the AMTEC are discussed. The operation states of the AMTEC are optimized. The maximum efficiency and power output density of the AMTEC are calculated. The selective criteria of the thickness of the electrolyte and other parameters are optimally provided. Moreover, it is expounded that the proportional coefficient related to the thickness of the electrolyte is closely dependent on electrolyte materials. The effects of this coefficient on the efficiency and power output density of the AMTEC are further discussed, and consequently, the rational range of the coefficient is determined.

A new model of the energy selective electron (ESE) device composed of four electron reservoirs and four energy filters is proposed. The device can work as a thermal amplifier, which may be equivalent to a coupling system consisting of two three-electron-reservoir heat pumps. Expressions for the heat-pumping rate (HPR) and coefficient of performance (COP) of the device are analytically derived through the heat flows of two-terminal ESE devices. The maximum HPR and COP are calculated. It is found that the maximum HPR of the coupling system can attain 2 times of that of a three-electron-reservoir heat pump while its COP is still equal to that of a three-electron-reservoir heat pump. Moreover, the effects of the chemical potentials of electron reservoirs, central levels of energy filters, half width at half maximum of energy filters on the HPR and COP of the device are discussed in detail. The optimal configuration of the device is determined. The cut-off value of the half width at half maximum of energy filters is calculated. The optimum selection criteria of main parameters are provided.

Two ruthenium complexes [Ru(MeIm)4(bpy)]2+ (Ru1, MeIm = 1-methylimidazole, bpy = 2,2′-bipyridine) and [Ru(Im)4(bpy)]2+ (Ru2, Im = imidazole) with the same PF 6 − counter-ion but different lipophilicities were synthesized and characterized and as potent anticancer agents. The relationships between cellular uptake, localization and molecular action mechanisms of these complexes were elucidated. The results showed that Ru1 with higher logPo/w exhibited faster cellular uptake rates, but lower anticancer activity than Ru2. In addition, Ru1 predominantly accumulated in the mitochondria and cytoplasm, and induced G0/G1 cell cycle arrest, whereas the more hydrophilic Ru2 tended to localize and accumulate in the cell nucleus and mitochondria. Further mechanism studies indicated that Ru2 caused cell cycle arrest at S phase by regulating cell cycle related proteins and induced apoptosis in A549 cells through DNA damage, cellular ROS accumulation, activation of the caspase pathway and mitochondrial dysfunction.