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Composites of organic small molecules (OSMs) and single-walled carbon nanotubes (SWCNTs) have drawn great attention as flexible thermoelectric (TE) materials in recent years. Here, we synthesized thieno[2′,3′:4,5]thieno[3,2-b]thieno[2,3-d]thiophene (TTA) and 2,6-dibromothieno[2′,3′:4,5]thieno[3,2-b]thieno[2,3-d]thiophene (TTA-2Br) and compounded them with SWCNTs, obtaining thermoelectric TTA/SWCNT and TTA-2Br/SWCNT composites. The introduction of the electron-withdrawing Br group was found to decrease the highest molecular orbital energy level and bandgap (Eg) of TTA-2Br. As a result, the Seebeck coefficient (S) and power factor (PF) of the OSM/SWCNT composite films were significantly improved. Moreover, suitable energy barrier between TTA-2Br and SWCNTs facilitates the energy filtering effect, which further enhances thermoelectric properties of the 40 wt % TTA-2Br/SWCNT composite film with optimum thermoelectric properties (PF = 242.59 ± 9.42 μW m–1K–2at room temperature), good thermal stability, and mechanical flexibility. In addition, the thermoelectric generator (TEG) prepared using 40 wt % TTA-2Br/SWCNT composite films and n-type SWCNT films can generate an output power of 102.8 ± 7.4 nW at a temperature difference of 20 °C. This work provides new insights into the preparation of OSM/SWCNT composites with significantly enhanced thermoelectric properties.

The fabrication of flexible high-performance organic/inorganic thermoelectric (TE) composite films has been a hot spot for researchers in recent years. In this work, dynamic 3-phase interfacial electropolymerization of aniline, together with physical mixing with single-walled carbon nanotubes (SWCNTs), was adopted to prepare polyaniline/SWCNT (PANI/SWCNT) TE composites. The dimethyl sulfoxide (DMSO) added into the electrochemical polymerization system affords strong capability in improving the TE performance of composite films. Moreover, varying loadings of SWCNTs can also conveniently tune the TE performance of composites. Hence, the resultant composites afford the highest power factor (PF) of 236.4 ± 5.9 μW m–1K–2at room temperature. This work demonstrates that the introduction of DMSO into the electrolyte and the electrochemical polymerization are highly effective in fabricating high-performance PANI/SWCNT TE composites.

Electrochemical polymerization has proven very effective in fabricating flexible organic/inorganic composite films with high thermoelectric (TE) performance. In this work, dynamic three-phase interfacial electropolymerization of 3,4-ethylenedioxythiophene (EDOT) combined with physical mixing of single-walled carbon nanotubes (SWCNT) and tellurium nanowires was employed to prepare PEDOT/Te/SWCNT thermoelectric composites. When the loadings of Te and SWCNT were changed, the electropolymerized PEDOT exhibited great capability of improving TE properties of the resultant composites with a highest electrical conductivity (σ) of 900.3 ± 20.5 S cm–1and Seebeck coefficient (S) of 43.4 ± 0.6 μV K–1, affording maximum power factor (PF) of 169.8 ± 7.8 μW m–1K–2at room temperature.

Aim: The aim of this study was to assess the accuracy of post-operative ultrasound examination for predicting wrist radio-cephalic arteriovenous fistula maturity.Methods: All radio-cephalic arteriovenous fistulas performed in our hospital between October 2015 and December 2017 were included in this study. Ultrasound examination of radio-cephalic arteriovenous fistulas was performed 2 weeks post-surgery. Radio-cephalic arteriovenous fistula maturation was defined as successful cannulation of a fistula with two needles, delivery of blood via the access route at a flow rate ⩾200 mL/min for 4 h, and dialysis via fistulae in at least six consecutive sessions.Results: Eighty-two wrist radio-cephalic arteriovenous fistulas were analyzed, of which 13 failed. Cephalic vein diameter >4.285 mm and brachial artery peak systolic velocity >134.75 cm/s were the best post-operative ultrasound predictors of radio-cephalic arteriovenous fistula maturity (p< 0.001 and p= 0.011, respectively). Receiver-operating characteristic curve analysis showed that the sensitivity and specificity of predicting radio-cephalic arteriovenous fistula maturation were 88.4% and 92.3% for cephalic vein diameter (area under the curve = 0.939), respectively, and 82.9% and 76.9% for brachial artery peak systolic velocity (area under the curve = 0.830), respectively. All assessments predicted radio-cephalic arteriovenous fistula maturity (post-operative positive predictive values: cephalic vein diameter = 98.4%, brachial artery peak systolic velocity = 95%) much better than radio-cephalic arteriovenous fistula failure (post-operative negative predictive values: cephalic vein diameter = 60%, brachial artery peak systolic velocity = 45.5%).Conclusion: Two weeks after surgery, a new wrist radio-cephalic arteriovenous fistula with a cephalic vein diameter >4.285 mm was considered suitable for dialysis. A high-risk arteriovenous fistula failure would benefit from early intervention.

This paper describes the adaptation of an upper-division undergraduate seminar course taught at the University of Missouri in Columbia (MU) to the Summer School Program of the University of Chinese Academy of Sciences in Beijing (UCAS). The course “Scientific Writing in Chemistry” addresses an essential need for science students across the globe to receive experiential education in scientific writing. An assignment-based curriculum was developed to instruct students on best practices in writing a scientific paper and to educate students about the scientific publication process and peer review. The semester-long MU course that included three meetings per week and had low enrollment was adapted to 20 h UCAS block courses with much higher enrollments. The drastic differences in scale and mode of delivery posed numerous nontrivial challenges and required modifications of the teaching goals. Because of the short duration of the summer courses, the MU curriculum with its focus on “working on assignments and working with rubrics” was adjusted to a curriculum which is based on “working with posted samples of completed assignments and working with rubrics” at UCAS. Instruction on publication ethics was emphasized, and several adjustments were made to address cultural and language differences. Enrollment data and results of evaluations collected over five years (2011–2016) are presented to demonstrate the success of the adaptation. It is hoped that this paper will contribute to the wide and open dissemination of this “Scientific Writing” curriculum and, more generally, that the example of our course adaptation might encourage outstanding experts from many science, technology, engineering, and mathematics (STEM) fields to contribute in a significant way to international education.

We report flexible films of organic–inorganic thermoelectric (TE) composites based on organometallic coordination compound [copper-phenylacetylide (PhC2Cu)] nanobelts and single-walled carbon nanotubes (SWCNTs). Interestingly, an unusual mechanochromic luminescence phenomenon from bright green to dark red is clearly observed after grinding the PhC2Cu crystalline nanobelts. The PhC2Cu/SWCNT composites display high mechanical flexibility and excellent TE performance. The maximum power factor at room temperature can reach as high as 200.2 ± 10.9 μW m–1K–2. The present study opens an avenue to fabricate novel organic–inorganic TE composite materials using organometallic coordination compounds such as PhC2Cu.

The catalytic fixation of greenhouse gas CO2has been a hot topic of research, in which the reduction and functionalization of CO2is important for application. In present work, cheap and readily available alkanolamines were used as efficient catalysts with phenylsilanes as reducing agents to achieve the N-formylation reaction by constructing C-N bonds via the reaction between CO2and amines (aliphatic or aromatic amines) under mild conditions (40℃and 0.1 MPa). Further studies showed that present catalytic system has wide substrates application. Mono-N-formylated compounds were obtained as main products with good to high yields for all amines. It is worthy noted that for p-aminobenzylamine containing two amino groups as substrate, both amino groups are formylated and N-formylation reaction occurs mainly in aliphatic amine with high electron cloud density. Scale-up research has been performed effectively with high conversion of amine (80%) to obtain the mono-formylated product selectively. Finally, the mechanism of the reaction between amine and CO2is proposed via control experiments and spectra verification. Systematic mechanism studies have revealed that after polarization by polar solvent DMSO, N-methyldiethanolamine activates CO2by forming internal salts, which are subsequently reduced by phenylsilanes to formoxysilane intermediates and finally to form N-formylated products.

ABSTRACTRibulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) is a key enzyme involved in CO2assimilation during photosynthesis. Rubisco activation depends on the activity of Rubisco activase (RCA). We performed 3′/5′ rapid amplification of cDNA ends (RACE) and reverse transcription polymerase chain reaction (RT-PCR) to amplify the 3′ and 5′ end sequences of RCA genes from hickory. We obtained two full-length gene sequences, designated CcRCAαand CcRCAβ. The two corresponding cDNAs are divergent in both the translated and 3′ untranslated regions. The analysis of the genomic DNA sequences suggested that the corresponding mRNAs are transcripts of two different genes and not the products of a single alternatively spliced pre-mRNA. We examined the expression of CcRCAαand CcRCAβin hickory leaves at various stages of development by quantitative real-time PCR (qRT-PCR) analysis. The results suggest that RCA genes play an important role in development and environmental responses. These results provide a basis for modulating RCA gene expression to improve the photosynthetic rate and plant growth in hickory.

Intelligent bionic leg (IBL) is an advanced trans-femoral prosthesis. First, the conception and structure component of IBL are introduced. Then, working principle of six-axis force sensor is analyzed in detail. The type selection and design of filter are discussed. In the end, the data filtering of low pass filter based on hamming window function is established and simulation is done. The simulation indicates that force and torque signal has a significant improvement after filtering and the filter designed in the paper is reasonable.

In the absence of sphere templates, hollow sodailte/NiO composite spheres were obtained by one-pot hydrothermal synthesis by using polyacrylamide hydrogels as "soft template". And the effect of nickel oxide content on the synthesis of hollow complex spheres was studied. The samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX). The results showed that when the content of nickel oxide was about 0.5%, the hollow sodalite/NiO composite spheres with high crystallinity, stable crystal, and obvious hollow structure could be successfully synthesized.

Layered AlPO4-5 molecular sieve was synthesized in polyacrylamide (PAM) hydrogels. The sample was produced using synthesis gel with weight composition of 1.0Al2O3 : 1.8P2O5 : 1.2 triethylamine (TEA) : 18.0H2O : 2.2 acrylamide (AM). The synthesized layered AlPO4-5 molecular sieve had an average thickness of 2.5 μm, and each layer was approximate circle with an average diameter of 5 μm.

Hollow sodalite spheres were prepared in water-soluble polymer polyacrylamide hydrogels (PAM) which were used as "soft template". The samples were characterized by XRD and SEM. The influence of the contents of initiator (ammonium persulfate) and crosslinker (N,N’-methylene-bis-acrylamide) on the size and morphology of hollow sodalite spheres was investigated. The results showed that the pore sizes of hollow sodalite spheres significantly decreased and the shell thicknesses thickened as the amount of initiator increased. The amount of MBAM affected the crystallization of sodalite, stacked arrangement and hollow structure. When the amounts range of MBAM was 0.8%-1.6%, hollow sodalite spheres were non-friable and smaller than the others, and their arrangement was uniform and orderly.

The active power filter has two key link for harmonic current detection and respectively compensation current tracking. This article mainly aims at harmonic current detection link. Firstly, Analysis adaptive harmonic detection methods, then based on over to LMS (Least Mean Square) adaptive algorithm as the research object, in discussing the adaptive algorithm criteria. By comparing several simulation-based LMS algorithm to achieve the results of the filter,analyse the causes of the results.

There was a new down-hole BOP that was designed to control blowout effectively in exploiting petroleum gas. The BOP was a new blowout preventer with a good development prospect which can not only automatically shut underground, but also control and automatically discharge shut up-hole state on the ground. Through introducing structure and working principle of the BOP, as well as the finite element analysis of some key components, there has been showed that the down-hole blowout preventer met the strength requirements and had relatively high security. The down-hole blowout preventer with a simple structure can not only work reliably but also complete the act of preventing blowout and unlocking many times to prevent blowout effectively and to improve drilling operations safety and efficiency. It will have a bright development prospect.

Preparation technology of Zn- peptide complexes was studied and its effects on growth performance and serum biochemical indicators were investigated by feeding Oreochromis Niloticus with feedstuff containing Zn-peptide complexes. The optimal conditions of synthesis reaction for Zn-peptide complexes prepared by zinc with peptide were described in the following: pH 5.0, temperature 80℃, and mass ratio of peptide-Zn 4:1, reaction time 30 min. Under such conditions, yield of Zn-peptide complexes was up to 54%, chelating rate of Zn was 55%, and Zn content of the complex was 6.5×104 mg/kg. A new complex formed from Zinc with peptide was identified by spectrum analysis. The 49-day feeding experiment showed that the complexes remarkably increased specific growth rate, survival rate, content of lysozyme and activity of superoxide dismutase (SOD) and alkaline phosphatase (AKP). Feed conversion ratio was significantly reduced as the additive increased. The content of total protein, albumin, and globulin were elevated too. And growth performance, body immunity, anti-oxidation function of Oreochromis Niloticus was significantly increased while the amount of the additive was 2.4 ~ 4.8 g/kg feedstuff in the experiment.

With increasing popularity and great application prospects of flexible wearable electronics, organic thermoelectric (TE)materials have become one hotspot in view of energy recycling and environment protection. However, diversifying application scenarios and frequent movements impose inevitable damage to materials. Herein, the polyethylene (PE) matrix is used in compositing with poly(3,4-ethylenedioxythiophene) and single-walled carbon nanotubes, forming a unique conductive penetration network and endowing the composites with a maximal room-temperature power factor of 158.81 μW m–1K–2with 20 wt % of PE. The introduction of PE not only reduces thermal conductivity (out-of-plane) but also provides the composites with self-healing and good mechanical properties. The compounding method and penetration structure reported in this work are universal and enlightening in developing highly efficient TE composites with cost-effectiveness and good comprehensive properties for low-grade waste heat utilization.

Aniline-pyrrole copolymer (poly(ANi-co-Py)) electropolymerized on conductive glass was ultrasonically mixed with single-walled carbon nanotubes (SWCNTs) to prepare poly(ANi-co-Py)/SWCNT thermoelectric (TE) composites. Effects of SWCNTs contents and reaction parameters on morphology, structure, and TE properties of composites are investigated. In the as-prepared flexible poly(ANi-co-Py)/SWCNT composite films, SWCNTs and poly(ANi-co-Py) are fully entangled and tightly bonded. The highest electrical conductivity (σ) of of 1035.3 ± 9.0 S cm−1is obtained at 60 wt% of SWCNTs. The maximal Seebeck coefficient (S) of 33.0 ± 3.2 μV K−1appears at 90 wt% SWCNTs. Thus, The peak room temperature power factor (PF) of the composites is 83.2 ± 3.3 μW m−1 K−2at 60 wt% SWCNTs. Improved TE performance of the composites reflects increased chain ordering and enhanced interaction between SWCNTs and poly(ANi-co-Py).

During an outbreak of hemorrhagic fever with renal syndrome in the Anhui Province of China, a door-to-door survey was conducted of all of the 10,024 residents of eight village communities. The incidence rates were higher in males than in females and higher in adults than in children. Of all the residents surveyed, however, those who had slept on the ground or had been engaged in heavy farm work were at a significantly higher risk of illness than were those who slept on wooden beds or did light work. Among men who did heavy farm work and who gave a history of sleeping in straw huts on the drained swamp, the attack rate was 2.33 times higher than it was for those sleeping exclusively in their permanent homes. Among both sexes, threshers had a significantly higher attack rate than did nonthreshers. Suspicions that trombiculid mites or gamasoid mites act as vehicles of transmission cannot be accepted as an explanation for the association of the risk of illness with the type of work done and with sleeping arrangements. Circumstantial evidence supports our hypotheses of airborne transmission and transmission by inoculation of infectious materials into skin lesions.