Potential application of a novel building-integrated solar facade water heating system in a subtropical climate:A case study for school canteen

The design and potential application analysis of the novel solar-absorbing integrated facade module and its corresponding building-integrated solar facade water heating system are presented in this study.Compared with the conventional building envelope,the main novities of the proposed facade module lie in its contributions towards the supplied water preheating to loads and the internal heat gain reduction.Besides,the proposed building-integrated solar facade water heating system broadens the combination modes of the solar thermal system and the building envelope.A dynamic model is introduced first for system design and performance prediction.To evaluate the energy-saving potential and feasibility of the implementation of the proposed facade module,this paper carried out a suitable case study by replacing the conventional facade module in the ongoing retrofitting project of a kitchen,part of the canteen of a graduate school.The detailed thermal performances of three system design options are compared in the typical winter and summer weeks and throughout the year,and then,with the preferred system design,the economic,energy,and environmental effects of the proposed system are evaluated.It was found that the system with a high flow rate of the circulating water is suggested.The annual electricity saved reaches 4175.3 kWh with yearly average thermal efficiency at 46.9%,and its corresponding cost payback time,energy payback time,and greenhouse gas payback time are 3.8,1.7,1.7 years,respectively.This study confirms the feasibility and long-term benefits of the proposed building-integrated solar facade water heating system in buildings.

中国上市公司资本投资效率——区域比较、行业差异与影响因素

本文采用中国沪深两市1998—2012年A股上市公司的数据,结合Wurgler（2000）和Richardson（2006）对资本投资效率的测度方法,分别从省级、行业和时间序列层面对中国上市公司资本投资效率进行测度,并在此基础上,从省级、行业和时间序列层面全面考察影响中国上市公司资本投资效率的因素。结果表明,整体上,中国上市公司资本投资效率较低;上市公司资本投资效率在不同的省份、行业和年度上均存在较大的差异。企业特征因素、财务因素与公司治理因素对中国上市公司资本投资效率的影响在不同省份、行业和年度呈差异性特征。我们还发现,相比于制度因素对各省份上市公司资本投资效率的有限影响,企业内部因素和行业因素的影响更大。

Rational design and biomedical applications of DNA-functionalized upconversion nanoparticles

Lanthanide-doped upconversion nanoparticles （UCNPs） offer unique advantages in term of low autofluorescence, high signal-to-noise ratio and deep tissue penetration, and have attracted considerable attention in biomedical applications. DNA, beyond the properties of self-assembly, also exhibits multiple functions such as molecular recognition, drug loading capacity and therapeutic effect. In this regard, the combination of UCNPs and DNA offers a promising and powerful platform for potential applications in biosensing, bioimaging and disease therapy. In this review, we mainly introduce recent progresses of DNA-functionalized upconversion materials, providing an overview of the design and applications in biosensing, bioimaging and therapy. The challenges and future perspectives are also discussed, aiming to promote their applications in material science and biomedicine.

Theoretical study of spin-orbit coupling and zero-field splitting in the spin-forbidden two-state reaction between cobaltacyclopentadiene and isocyanate

The two-state reaction mechanism of CpCo(C_4H_4)with isocyanate on the triplet and singlet potential energy surfaces has been investigated at the B3LYP level.A study is described for the computation of spin-orbit coupling of triplet state of the minimal energy crossing point(CP)with their singlet states and of the zerofield splitting(ZFS)parameters of the triplet states,including the full one-and two-electron terms of the BreitPauli Hamiltonian.There are two key crossing points along this two-state reaction pathway.The first crossing point—CP2 exists near^1B.The reacting system will change its spin multiplicity from the triplet state to the singlet state near this crossing region.Although the spin-orbit coupling interaction and ZFS D-tensor of the CP2 region are very strong,the reaction system will occur the reverse intersystem crossing from T_1 to S_0.Therefore,its spin-flip efficiency may be lower.The second crossing point,CP3will again change its spin multiplicity from the singlet state to the triplet state in the Co-Cr bond activation pathway,leading to a decrease in the barrier height of^1TS(CF)from19.5 to 9.5 kcal/mol(1cal=4.182 J),and the efficiency of intersystem crossing from S_0 to T_1 is high because the larger spin-orbit coupling(SOC)matrix elements will result in the overpopulations of the three sublevels of T_1(3.30×10^(-1),3.32×10^(-1),and 3.38×10^(-1),respectively).