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The construction industry is a pillar industry of China's national economy but its problems of high energy consumption, high pollution, and low energy efficiency are increasingly prominent. The study on the energy efficiency of the construction industry is of great significance for improving development quality and achieving the goal of energy saving and emission reduction. In this paper, a three-stage undesirable SBM-DEA model was employed to measure the energy efficiency in the construction industry during 2005-2016. The CO2 directly emitted by the construction industry and indirectly emitted in the production of building materials were used as the undesirable output and the three-stage framework was employed to analyze and eliminate the influence of external environment. The empirical results showed that low efficiency of management in the construction industry is an important factor leading to the low level of energy efficiency in China's construction industry. For the energy efficiency value before and after adjustment, the "high-high" provinces have made full use of the superior external environment by their high management level, while the "high-low" provinces need to fully realize the potential in promoting energy efficiency of its external environment by improving its own management of the construction industry. On the contrary, the "low-high" provinces need to improve the external environment to ease its restrictions on the level of management in the construction industry. Environmental factors and management level should be considered simultaneously for different provinces to improve energy efficiency of the construction industry.

With monthly average temperature series in the contiguous United States during the period from January 1895 to July 2018, the author uses wavelet analysis to investigate possible connection between the average temperature and solar activity. The results show obvious fluctuation characteristics in the temperature series. The modulation action from solar activity plays an important role in the oscillation of the contiguous United States average temperature, and there is a possible association existing in the temperature series and solar activity on decade time scales.

In order to explore the interaction between meloxicam and trypsin, the interaction mechanism between meloxicam and trypsin was studied by fluorescence spectrum, UV-vis absorption spectrum, ...

The mechanism of interaction between cefonicid sodium and pepsin was investigated by various spectroscopic methods and molecular docking. Cefoncid sodium quenched the intrinsic fluorescence...

A colorimetric assay for acid phosphatase (ACP) was constructed that is based on in situ polymerization of aniline catalyzed by gold nanoparticles (AuNPs). Aniline can be polymerized by ammonium persulfate (APS) in acidic condition and form gold-polyaniline core-shell nanoparticles (Au@PANI NPs) in the presence of AuNPs with the assistance of sodium dodecyl sulfate (SDS). AuNPs were also found to accelerate the polymerization process of aniline and thus shorten the reaction time. Upon the introduction of ascorbic acid (AA), the oxidant APS was consumed via the redox reaction. That led to the suppression of the formation of PANI. Consequently, ACP activity can be supervised on the basis of hydrolysis of 2-phospho-L-ascorbic acid trisodium salt (AAP) catalyzed by ACP to release AA. With the increase of ACP activity, the intensity ratio of the absorbance at λ705 nm (A705) and the absorbance at λ530 nm (A530) gradually decreased and the color gradually changed from dark-green to light-green to blue-gray to purple and eventually to pink. This method for ACP determination worked in the range 0.40 to 2.00 U·L−1. The detection limit is 0.043 U·L−1. The assay was applied to determine ACP in human serum. The recovery ranged from 81.0 to 104.6%. Relative standard deviation was less than 5%. This suits the request for biological sample analysis.

Non-point source pollution from excessive use of fertilizers in agriculture is a major cause of the eutrophication problem in China. Understanding farmers’ decision-making concerning fertilization and identifying the influencing factors in this process are key to tackling overfertilization and related pollution issues. This paper reports a study on modelling decisions about fertilizer use based on data collected from 200 farmer households in the Three Gorges Reservoir area of China, using a well-fitted artificial neural network (ANN) with incorporated variance-based sensitivity analysis. The rate of fertilizer use estimated from the model is in good agreement with observed data. The model is further validated and tested by comparing the simulated and observed values. Results show that the model is able to identify the influencing factors and their interactions causing the variation in fertilizer use and to help pinpoint the underlying reasons. It is found that the farmers’ fertilization behavior is greatly affected by the area of cultivated land, followed by the interaction among farmers’ education level, annual income, and awareness of the importance of environmental protection. Future land consolidation is one of several ways to achieve more sustainable fertilization strategies.

In the past few years, we have gained a better understanding of the information processing mechanism in the human brain, which has led to advances in artificial intelligence and humanoid robots. However, among the various sensory systems, studying the somatosensory system presents the greatest challenge. Here, we provide a comprehensive review of the human somatosensory system and its corresponding applications in artificial systems. Due to the uniqueness of the human hand in integrating receptor and actuator functions, we focused on the role of the somatosensory system in object recognition and action guidance. First, the low-threshold mechanoreceptors in the human skin and somatotopic organization principles along the ascending pathway, which are fundamental to artificial skin, were summarized. Second, we discuss high-level brain areas, which interacted with each other in the haptic object recognition. Based on this close-loop route, we used prosthetic upper limbs as an example to highlight the importance of somatosensory information. Finally, we present prospective research directions for human haptic perception, which could guide the development of artificial somatosensory systems.

Concentration-dependent photoluminescence carbon dots (CDs) have been successfully synthesized through the one-step hydrothermal treatment of o-phthalic acid and ethylenediamine. The CDs possessed higher fluorescence quantum yield, up to 39.22%, exhibiting distinguished optical property, water solubility, and stability. The CDs that emit strong blue-green fluorescence can visually identify and determine tetracycline (TC), oxytetracycline (OTC), and chlortetracycline (CTC). TC quenched the fluorescence of CDs at 500 nm owing to the inner filter effect; OTC behaved similarly, but the emission wavelength of CDs was red-shifted to 515 nm. Inversely, once CTC was introduced to CDs solution, the fluorescence increased and the emission peak was blue-shifted to 450 nm. Bandgap transition and electrostatic interaction were proposed to be the mechanisms for the detection of OTC and CTC by CDs. Wide linear relationships were established for TC, OTC, and CTC with the limits of detection to be 50 nM, 36 nM, and 373 nM, respectively. Furthermore, the nanoscale probe constructed by this system has been applied to detect tetracyclines (TCs) in complex samples with satisfying recoveries (93.2–114%) and was designed as a portable test strip sensor for visually on-site TCs of honey sample screening. Accordingly, the preparation process of the nano fluorescent probe is simple and environmentally friendly, and the probe has a specific recognition ability for tetracyclines. The synthesized CDs in this work provide a new orientation for fast, effective, and visual real-time detection of tetracycline in actual samples.

Gold nanoparticles (AuNPs) catalyze the mild reaction between the weak reducing agent kojic acid (KA) and silver ions (Ag+) to form Au@Ag bimetallic NPs by the combination of the intrinsic catalysis with plasmonic properties This is proposed as a novel optical assay to determine the tyrosinase (TYRase) concentration. The nanoparticles have been characterized by UV-vis spectroscopy, transmission electron microscope (TEM) images, and X-ray photoelectron spectroscopy (XPS). The sensing mechanism is based on the fact that KA binds to TYRase by chelating with dicopper active site of TYRase and the introduction of TYRase restrains the Au@Ag bimetallic NP formation by the precedent binding with KA. A clear color variation from yellow to pink and UV-vis spectral changes are observed at the optimal wavelength of 410 nm. The assay works in the range 0.13~0.73 U mL−1 with a detection limit (LOD) of 0.019 U mL−1. The impact from matrix interfering substances including glucose, uric acid, common oxidases, and amino acids is negligible. The applicability is demonstrated by quantitative determination of TYRase in human serum samples with 74 to 89% recovery and RSD less than 4.0%, which accords with the level for bio-sample analysis.

The interaction of pioglitazone hydrochloride bound to tryptophan residues and tyrosine residues in bovine transferrin was investigated using synchronous fluorescence spectroscopy at various temper...

The interaction mechanism between nifedipine (NDP) and pepsin (PEP) at 298, 310, and 318 K was studied by various spectroscopic techniques and molecular docking. The experimental results showed that NDP mainly quenched the fluorescence of PEP by dynamic quenching of non-radiative energy transfer, but no significant changes in the secondary structure of PEP. The protein binding rate (W) of NDP measured at 310 K was 71.79–89.15%, and a binding rate model of NDP and PEP was established, W = − 0.1273R2 − 0.0519R + 0.8973. Hill’s coefficients were approximately 1, which showed that the interaction of NDP and PEP will not affect the binding of subsequent drug to the protein. The molecular docking technique was used to simulate the interaction between NDP and PEP, the results demonstrated that the binding site of NDP is located in the active center of pepsin, which was consistent with the conclusion of the spectroscopic method, and it was also proved that the interaction of PEP–NDP system was driven by hydrophobic and hydrogen bonding.

Taking advantages of reticular proteins and reductive groups on the surface, eggshell membrane (ESM) was selected to synthesize MnO2 nanoparticles from potassium permanganate through a super simple way in which ESM acted as both template and reductant. This process avoided harsh reaction conditions or complicated aftertreatments and thus owned the merits of green synthesis, handy operation, low cost, and easy purification. The ESM-templated MnO2 nanoparticles (MnO2 NPs/ESM) were characterized, and the content of nanomaterials on the template was tested. MnO2 NPs/ESM showed a good capacity for decontamination of tetracycline hydrochloride (TCH). The macroscopical materials can be separated easily by taking the membrane out to stop the degradation instead of centrifugation or filtration. It was studied that 72.27% of TCH (50 mg/L) was decontaminated in 20 min by 0.1920 g/L MnO2 nanoparticles, and removal efficiency could reach 83.10% after 60 min under buffered condition. The kinetics was studied with or without buffer, and it was concluded that the degradation process followed a pseudo-second-order model. The facile synthesis of materials and effective degradation would facilitate the nano-MnO2-based decontamination applications.

The extent to which drugs combine with trypsin is influenced by the interaction of tartrazine and trypsin, which may cause overdose or underdose of drugs. Therefore, the interaction of tartrazine and trypsin is investigated by methods of spectrometry in this paper. The binding rate of tartrazine to trypsin is 80.95–95.71% at 310 K, and Hill’s coefficients are almost 1. The effect of tartrazine on trypsin structure was studied by synchronous and circular dichroism. The results showed that the binding of tartrazine and trypsin induced the conformational change of trypsin, and quenched the endogenous fluorescence in trypsin. The results of molecular docking revealed that tartrazine is located in the catalytic active site of trypsin, and is consistent with that of experimental calculation.

Distributed energy supply has a prominent impact on solving the contradiction between energy supply and demand, environmental degradation, and other issues. This paper analyzes the application of distributed energy supply for specific power projects. We developed a systematic post project evaluation index and evaluation model using the theory of matter-element extension, and determined weights for all indicators that influenced distributed energy generation projects, combined with the attribute hierarchical model. The proposed model was verified experimentally, and shown to enhance evaluation of distributed generation projects. In addition, (1) Distributed energy systems have been widely applied across the world due to their inherent advantages of flexibility, convenience, environmentally friendliness, and high reliability, so it is necessary to study. (2) This paper combined the matter-element extension theory (MEET) and the attribute hierarchical model (AHM) to develop an evaluation model for distributed generation projects. The proposed model was verified experimentally using actual distributed energy project data. (3) This paper enhances the evaluation theoretical research on the post-evaluation of distributed generation projects and capturing experience and lessons for subsequent projects.

An efficient scheme for controlled dense coding is presented with the aid of the introduction of auxiliary particles, appropriate local unitary operations and measurement basis. In this proposal, the four-qubits maximal slice state, which belongs to partially entangled states, is used as quantum channel. The concrete implementation procedures for our scheme with one sender, one receiver and two controllers are given in detail, and the average transmitted classical information from the sender to the receiver is calculated. Additionally, the physical realization of this proposal is discussed based on the optical elements.

The terahertz (THz) dielectric properties of super-aligned multi-walled carbon nanotube (MWCNT) films were characterized in the frequency range from 0.1 to 2.5 THz with terahertz time-domain spectroscopy. The refractive index, effective permittivity, and conductivity were retrieved from the measured transmission spectra with THz incident wave polarized parallel and perpendicular to the orientation of carbon nanotubes (CNTs), and a high degree of polarization dependence was observed. The Drude-Lorentz model combined with Maxwell-Garnett effective medium theory was employed to explain the experimental results, revealing an obvious metallic behavior of the MWCNT films. Moreover, rectangular aperture arrays were patterned on the super-aligned MWCNT films with laser-machining techniques, and the transmission measurement demonstrated an extraordinarily enhanced transmission characteristic of the samples with incident wave polarized parallel to the orientation of the CNTs. Surface plasmon polaritons were employed to explain the extraordinarily enhanced transmission with high accuracy, and multi-order Fano profile was applied to model the transmission spectra. A high degree of agreement was exhibited among the experimental, numerical, and theoretical results.

Molecular imprinting technology was used to coat polydopamine (PDA) onto MIL-53(Fe) surface by simple self-polymerization. The MIL-53(Fe)@MIP composite with enhanced peroxidase-like activity and specific target recognition function was synthesized and selected to construct a fluorescence sensor to detect metronidazole (MNZ). Since the substrate terephthalic acid was incorporated in the framework of MIL-53(Fe)@MIP, no additional luminescent substrate was required. This avoided the interference of the substrate on the enzymatic detection system and improved the accuracy of the assay. The characteristics of MIL-53(Fe)@MIP composite were investigated and confirmed by systematic analyses. The experimental results proved that the sensor provided satisfactory performances for quantitative determination of MNZ in wide linear range from 1 to 200 μM with low limit of detection as 53.4 nM. Potential interfering substances such as common cations and anions, amino acids, other antibiotics, sugars, and food additive were studied to show negligible effect on the assay, allowing the practical application to different fields including milk and human serum by the standard addition method. The recoveries were obtained between 93.2 and 102%, and the RSD was less than 3%.

This study aims to investigate the interaction between glipizide and bovine hemoglobin using fluorescence quenching, circular dichroism spectroscopy in various temperatures (293, 303, and 3...

The Pacific Decadal Oscillation (PDO) is an El Nino-like pattern of Pacific climate variability, oscillating between its warm and cool phase about every 20–30 years as defined by oceanic temperature anomalies in the northeast and tropical Pacific Ocean. In this work, the authors investigate the possible connection between the PDO and solar activity by means of wavelet technique. The study shows obvious fluctuation characteristics in the PDO series. The modulation action from solar activity plays an important role in the oscillation of the Pacific, and there is a possible association existing in the PDO and solar activity on decade time scales.

Eggshell membrane (ESM) is selected as biotemplate to prepare MnO2 submicroparticles (SMPs) using Chinese Brush with sodium hydroxide solution. The size with average 710 nm of the obtained materials is in good consistency with the microsructured biotemplate. An efficient and convenient absorbent for methylene blue (MB) is developed. The removal efficiency could reach up to 93% in 35 min under room temperature without pH adjusting owing to the excellent adsorption from ESM itself and hydroxyl group formed on the surface of MnO2 crystal in the aqueous solution. Materials on the membrane can be separated from the wastewater simply to avoid the secondary pollution caused by the leak of material. This interesting approach to MnO2 SMPs and facile operation for MB adsorption could open a new path to the submicro-materials based wastewater treatment.

We propose an efficient scheme for joint remote state preparation (JRSP) of arbitrary multi-qubit states from two senders to one receiver with the 100% successful probability. Quantum channel is composed of maximally three-qubit entangled states, and several special mutually orthogonal measurement basis are constructed without the introduction of auxiliary particles. We also calculate the total classical communication cost required in the JRSP processes. The concrete JRSP procedures for remotely preparing single-qubit and two-qubit states are illustrated to prove explicitly the feasibility of this JRSP protocol.

In this paper, an efficient scheme of remotely preparing four-qubit quantum states via two-qubit maximally entangled states is proposed. This scheme can be accomplished by using appropriate unitary transformations and some classical communication. The detailed processes for preparation of four-qubit states are presented in the general case and two special cases, respectively. The method of constructing special measurement basis in general case is provided, and the similar methods for real-parameter state case and equatorial state case are also discussed. Meanwhile, the probabilities of successful preparation under each case are calculated in our schemes. The results show that the successful probability is only 1 / 16 in the general case, and the probability can reach up to 100% when the relative phase factors are zero or the amplitude parameters are 1 / 4.

To well satisfy the newly emerging personalized electronics, it is urgent to develop durable and reliable flexible energy storage devices having a favorable match with them. However, conventional polymer matrixs based hydrogel electrolytes inevitably limit the development of desired supercapacitors due to their poor stretchable, healable as well as electrochemical properties. Here, a novel multifunctional hydrogel polyelectrolyte (VHSNPs-PAA/H2SO4/ARS) is developed comprising the alizarin red S (ARS) redox mediator and the double cross-linked polyacrylic acid (PAA) by the vinyl hybrid silica nanoparticles (VHSNPs) and hydrogen bonds, which realized the combination of ultrahigh stretchability (~2400% strain), robust mechanical toughness (lift up the 500 g weights), favorable self-healability (~92% efficiency during 10 cutting/healing cycles), high ionic conductivity (33 mS cm−1), powerful self-adhesiveness and superior redox activity within a single hydrogel structure. The facilely fabricated carbon-based supercapacitor using the obtained hrdrogel as the electrolyte can achieve large electrode specific capacitance of 248 F g−1 and high mass energy density of 16.7 W h kg−1, which are much larger than the recently reported stretchable and self-healing hydrogel electrolytes based flexible supercapacitors. Meanwhile, as-fabricated device also exhibits the excellent cycling stability and superior durability against physical deformation after 5000 charge-discharge cycles and 200 bending-releasing cycles, respectively.

In this article, two Keggin-type polyoxometalates [Co(L)2]3[PMo12O40] (1) and [Co(L)2]3[PW12O40] (2) (HL = 2-acetylpyrazine thiosemicarbazone) were prepared and fully characterized. The compounds are stable in aqueous solution with different pH values and show superior antibacterial activity against Escherichia coli (E. coli: minimal inhibitory concentration (MIC) = 0.00375, 0.12 μg/mL), Agrobacterium tumefaciens (A. tumefaciens: MIC = 0.06, 0.12 μg/mL), Bacillus subtilis (B. subtilis: MIC = 0.015, 0.06 μg/mL) and especially for Staphylococcus aureus (S. aureus: MIC = 0.00048, 0.015 μg/mL) for 1 and 2, respectively. The time kill studies showed the entire killing of specific bacteria during 4 to 8 h. In addition, the possible antibacterial mechanism of compound 1 was explored systematically. The experimental results proved that cell wall/membrane damage, leakage of protein, inhibition of respiratory chain dehydrogenases activity, enhancement of intracellular reactive oxygen species (ROS) and depletion of glutathione (GSH) were the potential causes of bacteria death.

Feature pyramid is a basic component in recognition systems for detecting objects of different scales. In order to construct the feature pyramid, most existing deep learning methods combine features of different levels based on a pyramidal feature hierarchy (e.g. SSD, Faster-RCNN). However, it lacks attention to those informative features. In this paper, we propose a gated feature pyramid network (GFPN) extracting informative features to enhance the representation ability of feature pyramid. GFPN consists of gated lateral modules and a top-down structure. The former automatically learns to focus on informative features of different scales, and the latter is used to combine the refined features. By using GFPN on SSD, our method achieves 80.1 mAP on VOC 2007 with an inference time of 11.9 ms per image, which improves the accuracy of FPN applied to SSD by 0.5% and adds marginal efficiency cost.

Peel browning spots (PBS) is a chilling injury (CI) symptom in cold-stored ‘Huangguan’ pear. In the present study, the effect of exogenous ethylene on CI and its correlation to proline and reactive oxygen species (ROS) metabolism was investigated. The results showed that ethylene treatment (100 μL L−1 for 24 h) could completely inhibit PBS appearance without significantly affecting fruit firmness, soluble solids content (SSC) and titratable acidity (TA), enhance ethylene production rate at the initiate stage of storage, and promote proline accumulation by increasing activities of pyrroline-5-carboxylate synthetase (P5CS), ornithine-delta-aminotransferase (OAT) and up-regulating expression of P5CS1 and OAT1 genes, decreasing proline dehydrogenase (PDH) activity and the expression of PDH1 gene in peel. Moreover, the ethylene treatment suppressed the accumulation of H2O2, O2- and malondialdehyde (MDA), maintained higher levels of ascorbic acid (AsA) and glutathione (GSH), and meanwhile enhanced activities of superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX), as well as expression of the genes such as SOD1, CAT1, and APX1 which could encode these enzymes in peel. These results suggested that ethylene alleviated the CI of ‘Huangguan’ pear by promoting the proline accumulation and antioxidant activity of peel.

This article describes the operational principle of the satellite-based Chinese Area Positioning System (CAPS) and proposes a monopole antenna for a large anchored buoy platform in harsh marine environment. The proposed antenna is highly omnidirectional with sufficiently wide half-power beamwidth (HPBW) greater than 40˚ (i.e., not less than ±20° swing) by using a conical ground plane, taking into account the geostationary satellite position, link budget, sea conditions, volume and cost. The impedance bandwidth defined by 10 dB return loss is 750 MHz (5.60-6.35 GHz), and the main lobe direction and the half-power beamwidth are about 46° and 43° at the operating frequency 5.885 GHz, respectively. The antenna prototype has been installed on-site to test its performance in sea. The results confirm that the proposed antenna is a suitable candidate for a variety of CAPS applications in China.

Direct observations of solar activity are available for the past four century, so some proxies reflecting solar activity such as 14C, 10Be and geomagnetic variations are used to reconstruct solar activity in the past. In this present paper, the authors use rectified wavelet power transform and time-averaged wavelet power spectrum to investigate long-term fluctuations of the reconstructed solar activity series. Results show obvious a quasi ~500-year cycle exists in the past solar activity. Three reconstructed solar activity series from 14C variations confirm the periodic signals.

A sun outage is an interruption or distortion of satellite communication signals caused by interference from solar radiation. There is a serious interference to satellite communication services in a special period of time. In the present paper, a novel model for predicting sun outage that is effective and can greatly improve accuracy and precision of sun outage prediction of earth station in satellite communication is presented.