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In this work, we present a simple method to improve the thermoelectric performance of the RF sputtered bismuth telluride films by raising the power of deposition. The as-deposited samples synthesized under different powers were investigated and compared. It shows that the films prepared under relatively higher power conditions exhibit much higher electrical conductivity to result in a greater power factor accompanied with a minor drop in the Seebeck coefficients. A relationship is established between the improvement in thermoelectric performance and the decrease in crystallinity, which might also reduce the thermal conductivity. A maximum power factor of 5.65 &times, 10&minus, 4 W&middot, m&minus, 1&middot, K&minus, 2 at 470 K is obtained for the sample deposited under 50 W with its Seebeck coefficient being &minus, 105 &mu, V/K. The temperature-dependent behaviors of the samples are also looked into and discussed. This work might offer an in-situ and cost-effective approach to improve the performance of thermoelectric materials.

We propose a DNA nanomachine (simplified as MB-PP) by inserting molecular beacon into a padlock probe for the sensitive and specific detection of K-ras gene mutation. In the presence of target DNA, MB-PP is able to be cyclized by ligase because its two ends are pulled together by target species. In this case, rolling circle amplification (RCA) occurs via the extension of primer by polymerase on cyclized MB-PP (CMB-PP), and thus two complete binding sites of nicking endonuclease are obtained due to the formation of RCA product/CMB-PP duplex. Naturally, a steady stream of two types of nicked fragments flow out from continuous rolling CMB-PP nanomachine after introduction of nickase, one of which can in turn triggers strand-displacement amplification (SDA), leading to the dramatic accumulation of nicked fragments. As a result, even in the presence of a trace amount of wild target DNA, the fluorescence intensity will substantially increase. Utilizing this DNA machine, the K-ras gene can be detected down to 50 pM with the linear response range from 50 pM to 10 nM. Moreover, the point mutation existing in the codon 12 of K-ras can be easily distinguished from the wild type.

The detection of biomarkers is of crucial importance in reducing the morbidity and mortality of complex diseases. Thus, there is a great desire to develop highly efficient and simple sensing methods to fulfill the different diagnostic and therapeutic purposes. Herein, using tumor suppressor p53 gene as model target DNA, we developed a novel palindromic fragment-incorporated molecular beacon (P-MB) that can perform multiple functions, including recognition element, signal reporter, polymerization template and primer. Upon specific hybridization with target DNA, P-MBs can interact with each other and are extended by polymerase without any additional probes. As a result, hybridized targets are peeled off from P-MBs and initiate the next round of reactions, leading to the unique strand displacement amplification (SDA). The newly-proposed enzymatic amplification displays the detection limit as low as 100 pM and excellent selectivity in distinguishing single-base mutation with the linear response range from 100 pM to 75 nM. This is the simplest SDA sensing system so far because of only involving one type of DNA probe. This impressive sensing paradigm is expected to provide new insight into developing new-type of DNA probes that hold tremendous potential with important applications in molecular biology research and clinical diagnosis.

To improve the thermal stability of multilayered solar selective absorber, an atomic-layer-deposited (ALD) Al2O3 layer was adopted to suppress the diffusion of metal atoms from the bottom reflection layer. The designed film structure was as that: Cu (>100.0 nm)/Al2O3 (59.8 nm)/Cr (17.8 nm)/SiO2 (66.3 nm)/Cr (4.4 nm)/SiO2 (83.0 nm). Multi-target magnetron sputtering method was employed to fabricate Cu, SiO2, and Cr layers, while for the Al2O3 layer, it was prepared by ALD. The sample has a solar absorptance of about 95.4% and a thermal emittance of 0.196 at the temperature of 773 K. The sample with the Al2O3 barrier layer work stably at 500 °C for 72 h, demonstrating that the proposed multilayer solar selective absorber is suitable for applications at middle-temperature solar thermal conversion systems.

Solar selective absorbers have significant applications in various photothermal conversion systems. In this work, a global optimization method based on genetic algorithm was developed by directly optimizing the solar photothermal conversion efficiency of a nano-chromium (Cr) film-based solar selective absorber aiming to work at the specified working temperature and solar concentration. In consideration of the semi-transparent metal absorption layer employed in multilayered solar selective absorbers, the optical constants of ultrathin Cr film were measured by spectroscopic ellipsometer and introduced into the optimization process. The ultrathin Cr film-based solar selective absorber was successfully designed and fabricated by the magnetron sputtering method for the working temperature at 600 K and a solar concentration of 1 Sun. The measured reflectance spectra of the sample show a good agreement with the numerical simulations based on measured optical constants of ultrathin Cr film. In comparison, the simulated results by using the optical constants of bulk Cr film or literature data exhibit a large discrepancy with the experimental results. It demonstrates the significance of considering the actual optical constants for the semi-transparent metal absorption layer in the design of nano-metal film-based solar selective absorber.

The development of rapid approaches to detect prognostic markers is significant in reducing the morbidity and mortality of cancer. In this paper, we describe a rapid and specific biosensing platform for target DNA (p53 gene as a model) detection based on reverse strand displacement amplification (R-SDA). When the p53 gene is added, multifuctional molecular beacon (MMB) is unfolded via the hybridization with p53 gene. With the assist of Klenow fragment (KF) and Nt.BbvCI (the nicking endonuclease), p53 gene recycling could be initiated and considerable amount of complementary sequences for the MMBs (Nicked fragments, NFs) could be formed, generating enhanced fluorescence signal. Using this amplification strategy, the proposed biosensor displays the detection limit of 1 nM and a wide linear range from 1 to 100 nM, even if only one type of probe is involved. Notably, remarkable detection specificity for single-base mismatched target p53 gene is achieved. Moreover, the described biosensor also exhibited the stability in real biological samples (human serum). The rapid detection strategy can be performed less than 30 min without harsh reaction conditions or expensive nanoparticles. This biosensor shows great potential for application in clinic assay, especially, for early cancer diagnosis.

For rational utilization of industrial wastewater containing salt, this paper puts forward a method to evaporate and concentrate salty water by applicating no padding evaporative cooling tower. This paper has established a testing bench of evaporation and concentration of salt-containing wastewater and fresh water recovery system. The actual operating characteristic of the testing bench is also tested. Tests showed that evaporated quantity of water of the system ranged from 1.8 to 2.2t/h under the conditions of salt water inlet temperature between 30°C and 40°C.It proves that the proposed salt-containing wastewater treatment is feasible.

With the rapid development of urbanization,the building energy use increases rapidly, in order to guarantee the sustainable development of our country road, energy saving, low carbon, emission reduction work has become an urgent issue.Building energy consumption database is an important part of the construction of energy-saving work, In this paper, the aim is to establish the large-scale public building energy consumption database system in northeast cold area of , mainly introduced the database development tools, the choice of object oriented programming method , the system design process,treating the ground source heat pump system as the research object, this paper have had research and analysis on applicability of ground source heat pump system and established the evaluation system.

Due to phase change materials (PCMs) composition, machining error, measuring error and other factors, the PCMs thermal physical properties, geometric properties, etc are usually uncertain. As a result, phase change heat transfer process is an uncertainty heat transfer process. But at present, heat transfer characteristics research on phase change thermal storage are all based on certainty heat transfer models (Taken uncertainty factors as certainty factors). In this paper, it is considered factors uncertainty influencing phase change thermal storage heat transfer process. By looked on the variation scope of influence factors as "interval number", based on interval mathematics, perturbation method and finite difference method, "interval number" heat transfer model of phase change thermal storage is established. In this model, the uncertainty variables are decomposed into the sum of the nominal value and the deviation value. PCM uncertainty temperature field can be determined by calculated nominal value and the deviation value of PCM temperature field separately. Comparison between simulation results of the model and experimental data implies that it is necessary to consider influencing factors uncertainty in phase change thermal storage heat transfer analysis.

The accurate detection of cancer-related genes is of great significance for early diagnosis and targeted therapy of cancer. In this contribution, an automatically cycling operation of a functional overhang-containing molecular beacon (OMB)-based sensing system was proposed to perform amplification detection of the p53 gene. Contrary to the common molecular beacon (MB), a target DNA is designated to hybridize with a label-free recognition probe (RP) with a hairpin structure rather than OMB. In the presence of a target DNA of interest, the locked primer in RP opens and triggers the subsequent amplification procedures. The newly-developed OMB is not only capable of accomplishing cyclical nucleic acid strand-displacement polymerization (CNDP) with the help of polymerase and nicking endonuclease, but is also cleaved by restriction endonucleases, removing the quencher away from the fluorophore. Thus, the target DNA at an extremely low concentration is expected to generate a considerable amount of double-stranded and cleaved OMBs, and the quenched fluorescence is completely restored, leading to a dramatic increase in fluorescence intensity. Utilizing this sensing platform, the target gene can be detected down to 8.2 pM in a homogeneous way, and a linear response range of 0.01 to 150 nM could be obtained. More strikingly, the mutant genes can be easily distinguished from the wild-type ones. The proof-of-concept demonstrations reported herein are expected to promote the development of DNA biosensing systems, showing great potential in basic research and clinical diagnosis.

This paper presents a new method of palmprint recognition based on improved scale invariant feature transform (SIFT) algorithm which combines the Euclidean distance and weighted sub-region. It has the scale, rotation, affine, perspective, illumination invariance, and also has good robustness to the target's motion, occlusion, noise and other factors. Simulation results show that the recognition rate of the improved SIFT algorithm is higher than the recognition rate of SIFT algorithm.

The approach of combining the characteristics of palmprint image database with an improved adaptive binary segmentation which is based on gray-scale distribution and structure of the palmprint image is presented in this article. We use median filter to remove the cross and obscure parts of the breakpoint, take advantage of an improved global threshold algorithm to get the binarization image and carry out corrosion, swelling, edge extraction and boundary tracking. Then we use the Euclidian distance to get the region of interest(ROI) automatically. The simulation experiment results show that the method can extract the ROI of palmprint image effectively and eliminate the noise in palmprint image.