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Hole transporting materials (HTMs) play an unparalleled role in heightening the stability and photovoltaic performance of perovskite solar cells (PSCs). The organic small molecule spiro-OMeTAD is frequently utilized for HTM in PSCs. However, the raw spiro-OMeTAD without dopant would be harmful to the development of highly efficient PSCs, due to its unsatisfied hole mobility and conductivity. Therefore, we introduce an inorganic dopant (chromium trioxide, CrO3) into the lithium-salt doped spiro-OMeTAD. Because of the exclamatory oxidizability of CrO3, it can accelerate the oxidation of spiro-OMeTAD and thereby enhancing the hole mobility of HTM. The introduction of CrO3 not only substantially decreases the density of defects, but also adjusts spiro-OMeTAD energy band, and thus effectively suppresses the hysteresis and improving stability of PSCs. In the end, we obtained a power conversion efficiency (PCE) as high as 22.6% after doping CrO3 in spiro-OMeTAD. The facile, low cost and outstanding photovoltaic performance render CrO3 an excellent dopant for HTMs in PSCs.

Gaming behaviors are challenges to governments’ performance measurement systems. This paper presents a theory of the ways in which participatory management and goal ambiguity shape gaming behaviors...

Titania (TiO2) has wide applications in the realm of perovskite solar cells (PSCs). Because high-temperature processing severely limits the application of flexible and tandem devices, it is signifi...

The introduction of upconversion materials as spectral converter into photovoltaic devices to harvest and convert near infrared photons to visible photons that can thus be absorbed by perovskite layer is a promising strategy for enhancing the performance of perovskite solar cells. Hence, β-NaYF4:Yb3+/Er3+/Sc3+@NaYF4 rare-earth doped upconversion nanoparticles with core-shell structure are synthesized. The doped rare-earth ions Yb3+ and Er3+ convert near infrared light to red and green light, and the Sc3+ ions enhance the upconversion luminescence efficiency, which broaden the absorption range of solar irradiation and generate extra photocurrent in the solar cells. The surface defects of β-NaYF4:Yb3+/Er3+/Sc3+ is passivated by the even NaYF4 shell, which results in the obvious enhancement in upconversion emission intensity. Consequently, the perovskite solar cell based on the rare-earth doped upconversion nanoparticle mesoporous layer achieves a high power conversion efficiency of 20.19%, while the device based on TiO2 mesoporous layer gets an efficiency of 17.44%.

Hole-transport layer (HTL) plays a crucial role in the photovoltaic performance of perovskite solar cells (PSCs). In order to improve the function property of HTLs, we first use potassium permanganate (KMnO4) as a dopant for the oxidization of 2,2′,7,7′-tetrakis(N,N-p-dimethoxyphenylamino)-9,9′-spirobifluorene (spiro-OMeTAD). The reaction between KMnO4 and spiro-OMeTAD produces the oxidized-state spiro-OMeTAD, which enhances the conductivity and adjusts the energy level of HTL. The dual functions of KMnO4 dopant bring high photovoltaic performance of the devices. The planar PSC based on photoactive layer of mixed-cation–anion perovskite and hole-transport layer of spiro-OMeTAD doped with 1.0 mol % KMnO4 achieves a power conversion efficiency of 20.03%. Meanwhile, the hysteresis effect of the device is greatly suppressed. The simple and low-cost processing and significant performance improvement render this method promising.

While the microfluidic chips for cell stretching and real-time cell observations have so far been composed of three layers, the present work reports a two-layer one, which is, on the surface, not available due to the ‘inherent’ difficulty of unstable focusing on cells in the microscopic observation under the stretching operation, etc. Herein, this difficulty was overcome to a large extent, in the case of appropriate device parameters, which were determined based upon finite element analysis and orthogonal experimental design. The novel chip was fabricated and confirmed to work in frequency up to 2 Hz and stretching ratio up to 20%. We further performed uniaxial stretching experiments of human mesenchymal stem cells on an elastic polymer, polydimethylsiloxane, and the cells were found to be highly oriented perpendicular to the stretching direction. The short working distance on this simplified two-layer chip enabled clear observation of microtubules and stress fibers of cells under an optical microscope. We also tested radial stretching and gradient stretching as proofs of concept of the extendibility of this type of chip. Therefore, in spite of being simpler, the two-layer chip suggested in this study exhibited enhanced and versatile functions, and the present work has thus afforded a new methodology of fabrication of microfluidic chips for the study of cells on biomaterials under a mechanical stimulus.

For a high-performance perovskite solar cell (PSC), the electron transport layer (ETL) plays a prominent role in the transportation of photogenerated charge carriers from the perovskite layer to electrode. Herein, indium sulfide (In2S3) nanosheets are synthesized by solvent-thermal method; In2S3 ETL is prepared by spin-spraying technique, and planar PSC is thus fabricated. The morphology observation indicates that the as-prepared In2S3 ETL is compact, smooth, pinhole-free, and with an optimal thickness of 40 nm. The photoelectrical characterization reveals that, compared to TiO2 ETL, the In2S3 ETL has lower electron trap-state density, lower potential barrier for electron injection from the perovskite layer, higher electron mobility and electron extraction ratio at the In2S3/perovskite interface, smaller contact resistance, and charge recombination. The planar device fabricated with CH3NH3PbI3 perovskite and In2S3 ETL gains an impressive power conversion efficiency (PCE) of 18.83%, and the photovoltaic de...

Lead amine halide perovskite solar cells (PSCs) have become dominant photovoltaic research topic in this decade. Electron transport layer (ETL) play a crucial role on PSCs. Here, we use tin tetrachloride as Sn source to synthesize SnO2 nanocrystals in a simple hydrothermal method. The as-synthesized SnO2 is spin-coated on FTO substrate, and then sintered under low temperature to form the ETL of planar PSCs. The concentration of SnO2 spin-coating solution and sintering temperature have great influence on the ETL quality and charge transportation in PSCs. Through optimized treatment (0.15 M SnO2, 120 °C sintering), the high quality SnO2 ETL with a uniform coverage, appropriate thickness, less charge recombination and low resistance can be obtained. Based on the ETL, a planar PSC with FAxMA1−xPbI3 achieves a high power conversion efficiency (PCE) of 19.34%. In addition, the planar PSCs based on SnO2 exhibit a stable PCE output and slight hysteresis. These researches provide a low-cost, easy strategy to fabricate tin oxide, and present potential to replace traditional titanium oxide (TiO2) in PSCs in the future.

The edge coherent mode (ECM) is a promising operational regime in the Experimental Advanced Superconducting Tokamak (EAST). In order to understand the physical mechanisms of ECM thoroughly, the automatic recognition of ECM is necessary. In this work, we define an adaptive denoising inequality based on the variance, and propose a dual-channel convolution feature extraction model to obtain a visualized ECM feature on which to perform ECM recognition. The new ECM recognition approach proposed in this paper provides better performance than the ECM recognition approach based on the feature of the row information points in the spectrogram, in terms of both precision and recall. In addition, the proposed approach is compared to four classical deep learning algorithms, and is found to provide competitive performance with a small amount of data.

// Pengpeng Xia 1,2 , Agnes Hakyung Choi 1,2 , Zengping Deng 3 , Yuqian Yang 1,2 , Jing Zhao 1,2 , Yiting Wang 1,2 , Philip R. Hardwidge 4 and Guoqiang Zhu 1,2 1 College of Veterinary Medicine, Yangzhou University, Yangzhou, China 2 Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China 3 Nanjing Hospital of T.C.M, Nanjing, China 4 College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA Correspondence to: Guoqiang Zhu, email: // Keywords : MUC4, carcinoma, epithelial, tumorigenicity Received : April 23, 2016 Accepted : October 26, 2016 Published : November 04, 2016 Abstract The cell surface membrane-bound mucin protein MUC4 promotes tumorigenicity, aggressive behavior, and poor outcomes in various types of epithelial carcinomas, including pancreatic, breast, colon, ovarian, and prostate cancer. This review summarizes the theories and findings regarding MUC4 function, and its role in epithelial carcinogenesis. Based on these insights, we developed an outline of the processes and mechanisms by which MUC4 critically supports the propagation and survival of cancer cells in various epithelial organs. MUC4 may therefore be a useful prognostic and diagnostic tool that improves our ability to eradicate various forms of cancer.

As one kind of promising next-generation photovoltaic devices, perovskite solar cells (PVSCs) have experienced unprecedented rapid growth in device performance over the past few years. However, the practical applications of PVSCs require much improved device long-term stability and performance, and internal defects and external humidity sensitivity are two key limitation need to be overcome. Here, gadolinium fluoride (GdF3 ) is added into perovskite precursor as a redox shuttle and growth-assist; meanwhile, aminobutanol vapor is used for Ostwald ripening in the formation of the perovskite layer. Consequently, a high-quality perovskite film with large grain size and few grain boundaries is obtained, resulting in the reduction of trap state density and carrier recombination. As a result, a power conversion efficiency of 21.21% is achieved with superior stability and negligible hysteresis.

Tin oxide (SnO 2 ), as electron transport material to substitute titanium oxide (TiO 2 ) in perovskite solar cells (PSCs), has aroused wide interests. However, the performance of the PSCs based on SnO 2 is still hard to compete with the TiO 2 -based devices. Herein, a novel strategy is designed to enhance the photovoltaic performance and long-term stability of PSCs by integrating rare-earth ions Ln 3+ (Sc 3+ , Y 3+ , La 3+ ) with SnO 2 nanospheres as mesoporous scaffold. The doping of Ln promotes the formation of dense and large-sized perovskite crystals, which facilitate interfacial contact of electron transport layer/perovskite layer and improve charge transport dynamics. Ln dopant optimizes the energy level of perovskite layer, reduces the charge transport resistance, and mitigates the trap state density. As a result, the optimized mesoporous PSC achieves a champion power conversion efficiency (PCE) of 20.63% without hysteresis, while the undoped PSC obtains an efficiency of 19.01%. The investigation demonstrates that the rare-earth doping is low-cost and effective method to improve the photovoltaic performance of SnO 2 -based PSCs.

Hole transport materials (HTMs) play an important role in perovskite solar cells (PSCs). At present, the most frequent used HTM is spiro-OMeTAD. However, spiro-OMeTAD without dopants have low electrical conductivity and hole mobility. Therefore, the improvement of mobility and conductivity of hole transport layer (HTL) has become a crucial issue. Here, we introduce a dopant, thionyl chloride (SOCl2), to oxidize spiro-OMeTAD and generate more spiro-OMeTAD+. Under the same conditions, the optimized device doped with SOCl2 achieves a power conversion efficiency (PCE) of 20.76%, while the pristine one is only 18.13%. The doping of SOCl2 not only reduces the density of defect states at the interface between perovskite and HTL, but also suppresses the recombination of light-induced carriers. In addition, the stability of the PSCs based on SOCl2 is greatly improved, which can maintain 90% of the initial PCE for 31 days under ambient conditions. This work provides a simple and feasible strategy for dopant engineering of HTL to achieve efficient PSCs.

Metal amine halide perovskite solar cells (PSCs), as a promising next generation photovoltaic device, have undergone an unexpected swift growth in the past decade. However, the practical application of PSCs is still facing the challenge of improving efficiency and stability, and the interfacial defects at mesoporous scaffolds is the crucial bottleneck need to be solved. Here, to heal defects and enhance performance, we implement four advantageous designs, i.e. low-temperature processing, rare-earth ion doping, brookite TiO2 scaffolds, and SnO2 blocking layer. As a result, the binder-free and sinter-free processing generates a single crystalline phase, evenly distributed, mesoporous Sc3+ doped brookite TiO2 scaffold, which induces a uniform coverage, void-less and high-quality perovskite layer. The favorable energy level alignment, diminished defects and carrier recombination improve the performance of the device. Consequently, the PSC based on Sc3+ tailored brookite TiO2 scaffold achieves a power conversion efficiency of 21.75% with hysteresis-free and excellent UV stability.

This paper proposes a procedure of predicting channel characteristics based on a well-known machine learning (ML) algorithm and convolutional neural network (CNN), for three-dimensional (3D) millimetre wave (mmWave) massive multiple-input multiple-output (MIMO) indoor channels. The channel parameters, such as amplitude, delay, azimuth angle of departure (AAoD), elevation angle of departure (EAoD), azimuth angle of arrival (AAoA), and elevation angle of arrival (EAoA), are generated by a ray tracing software. After the data preprocessing, we can obtain the channel statistical characteristics (including expectations and spreads of the above-mentioned parameters) to train the CNN. The channel statistical characteristics of any subchannels in a specified indoor scenario can be predicted when the location information of the transmitter (Tx) antenna and receiver (Rx) antenna is input into the CNN trained by limited data. The predicted channel statistical characteristics can well fit the real channel statistical characteristics. The probability density functions (PDFs) of error square and root mean square errors (RMSEs) of channel statistical characteristics are also analyzed.

Channel modeling is of vital importance to the development and performance evaluation of wireless communication systems. Though many millimeter-wave (mmWave) channel models have been proposed, few of them concern about staircase environments. This paper analyzes the statistical characteristics of 60 GHz channels in a staircase environment with the transmitter (Tx) side fixed and the receiver (Rx) side moving, especially the variation of characteristics arising from the motion of receiver Rx. Fuzzy c-means (FCM) algorithm is applied in clustering procedure and the Kim-Park (K-P) index combined with the multipath component distance (MCD) are utilized to obtain the optimal cluster number. Simulation results show that almost all of the channel characteristics are related to the Euclidean distance between the Tx and Rx. Also, they are affected by building structures, which will provide guidance on the layout of communication devices.

A modified wideband and wide-beam Archimedean spiral antenna, with the characteristics of circularly polarization, four arms and mode-2 operation, is presented in this paper. The antenna features a modified cup-shaped cavity and a dielectric substrate with twelve metal patches printed on it. The simulated results show that the voltage standing wave ratio (VSWR) is better than 2 over the operating band of 8∼12GHz. The beamwidth of the modified spiral antenna is greatly broadened compared with the conventional antenna. Over the whole operating frequency band, the beamwidth of the modified Archimedean spiral antenna is about ± (15°∼75°).

Multichannel wavelength converters may be important components in the cross connects in future wavelength division multiplexing (WDM) optical network. We first present simulations of a scheme to perform dual-wavelength conversion of 16QAM signals based on four wave mixing (FWM) in semiconductor optical amplifier (SOA) without pump phase noise. The effectiveness of the proposed scheme is investigated by analyzing the spectrum diagram, constellation diagram and bit error rate (BER) of the output signal. BER measurements for four output channels show that power penalties are less than 1.2dB with respect to the input signals and small difference (

The article examines more than 80 winners and finalists in the Innovations and Excellence in Chinese Local Governance (IECLG) awards programme between 2001 and 2008. Our results show the main types of innovation in the Chinese public sector to be management, service and collaborative innovation, although instances of technological and governance innovation are emerging. State and party agencies at the city and county levels in eastern China appear to be more innovative than their counterparts at other levels in central and western China. We identify several factors that affect innovation in China, and find the country to have some distinct innovation characteristics relative to other countries. Our analysis contributes to an understanding of the state of the art in public sector innovation in China and suggests directions for further international comparative research.