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Accurate preoperative glioma grading is essential for clinical decision-making and prognostic evaluation. Multiparametric magnetic resonance imaging (mpMRI) serves as an important diagnostic tool for glioma patients due to its superior performance in describing noninvasively the contextual information in tumor tissues. Previous studies achieved promising glioma grading results with mpMRI data utilizing a convolutional neural network (CNN)-based method. However, these studies have not fully exploited and effectively fused the rich tumor contextual information provided in the magnetic resonance (MR) images acquired with different imaging parameters. In this paper, a novel graph convolutional network (GCN)-based mpMRI information fusion module (named MMIF-GCN) is proposed to comprehensively fuse the tumor grading relevant information in mpMRI. Specifically, a graph is constructed according to the characteristics of mpMRI data. The vertices are defined as the glioma grading features of different slices extracted by the CNN, and the edges reflect the distances between the slices in a 3D volume. The proposed method updates the information in each vertex considering the interaction between adjacent vertices. The final glioma grading is conducted by combining the fused information in all vertices. The proposed MMIF-GCN module can introduce an additional nonlinear representation learning step in the process of mpMRI information fusion while maintaining the positional relationship between adjacent slices. Experiments were conducted on two datasets, that is, a public dataset (named BraTS2020) and a private one (named GliomaHPPH2018). The results indicate that the proposed method can effectively fuse the grading information provided in mpMRI data for better glioma grading performance.

As the quickest access for readers to get the key of the content, news headline translation has aroused more and more researchers’ attention. Different from other studies on this subject, this paper studies the English to Chinese translation strategies of news headlines by analyzing 137 English to Chinese headlines concerning coronavirus pandemic from “Language Tips” in China Daily Website. The two translation strategies (imitation and variation) primarily adopted in the selected news headlines are clarified, and specific translation methods under these two strategies are further discussed based on Chesterman’s Translation Ethics.

In this research, collagen hydrolysates with different average molecular weights ( Mn ¯ ) from leather collagen were chosen as raw materials. Five environmental-friendly sizing agents (SA) were prepared by cross-linking collagen hydrolysates with glycol diglycidyl ether (GDE) and further grafting them with butyl acrylate (BA) and styrene (St). Then the compound sizing agents (SGDESA-x, x = 1, 2, 3 and 4) were obtained by simple physical mixing of GDESA and starch. The surface sizing performance of GDESA and compound sizing agents were studied. The research result shows that both physical, mechanical properties and water resistance of the corrugated paper coated by GDESA were significantly improved when Mn ¯ of collagen hydrolysate was about 10,000, and its emulsion exhibited robust stability in long standing time. Furthermore, when the SGDESA-2 was used as a sizing agent, the coated corrugated paper exhibited strong water resistance, good physical and mechanical properties even after refolded for 20 times.

The accuracy of English translation of construction texts ensures the implementation of cooperative projects with foreign parties. However, translators are prone to comprehension errors in the process of English translation, thus leading to illogic expressions in the target text. This paper first analyzes the illogic expression problems at lexical, syntactical and discourse level, then briefly introduces explication translation strategy. Finally, it proposes explication translation strategy in construction texts so as to achieve the effect of precise wording, concise expression and rigorous logic.

Chromotropic Acid Grafted Amphoteric Polyurethane (CAGAPU) was synthesized with Chromotropic Acid (CA) as a modifier for Polyurethane (PU). The structure of CAGAPU was confirmed by FT-IR, 1H-NMR. The retanning process and the experiments of CAGAPU with formaldehyde indicate the following: (1) The leather retanned by CAGAPU can be comparable or surpassed to the market PU-based retanning system in terms of shrinkage temperature and sensory performance. (2) The leather collagen fibers are smoother and orderly which provides a potential value for the appearance of the leather and fur industry. (3) The CAGAPU retanned system can bring down the free formaldehyde content in aldehyde tanned leather significantly. (4) The optimum dosage of CAGAPU is 20 g and the best retanning time is 6 h (5) The CAGAPU retanned system can reduce the free formaldehyde, Biochemical Oxygen Demand (BOD), Total Dissolved Solids (TDS) and Total Suspended Solid (TSS) from the source which retard pound on the economy and environment greatly compare to the traditional governance. Therefore, this paper provides the possibility for the sustainable development of leather. The work has changed the traditional way of “terminal treatment” and realized the “initial treatment” and may also offer a new idea of solving the problem of formaldehyde in the newly decorated houses or in the air.

The English translation of Chinese tea terminology not only facilitates tea export but also functions as a bridge for the international communication of tea culture. However, the lack of translation norms for tea terminology in China leads to various translation problems, resulting in the failure of international tea communication. Translation, as an important means of intercultural communication, requires the constraints of ethics. Based on five models of Chesterman’s translation ethics, in combination with the different translation tasks, this paper divided tea terminology into five corresponding categories and analyzed how Chesterman’s five translation ethics were applied in tea terminology translation. The results show that Chesterman’s translation ethics is applicable to improving the quality of tea terminology translation.

Abstract With the characteristics of controllable charge and environmental friendliness, amphoteric polymers can be used in post-tanning process to solve the problems that arise during leather making and are caused by the low absorption rate of single-charge chemicals, incompatibility with new tanning methods, and complex operation process. In this review, the structure, performance, and preparation of amphoteric polymers are reported. Then, the charge change of collagen during different tanning and pH treatments is introduced. Finally, the application and development of amphoteric polymers during the post-tanning process of leather making are discussed. This review has certain guiding significance to the preparation and application of amphoteric polymers for tanning system. Graphical abstract

The development of an ecological chrome-free tanning system is a research hotspot and is of great significance to green and sustainable leather production. However, most of the chemicals used in the system exhibit poor compatibility, which means the overall performance of chrome-free tanned leather is not comparable with that of chrome tanned leather. Moreover, the chemicals tend to exhibit poor biodegradability and cause pollution, which, of course, belies the original aim of green chrome-free tanning. With this in mind, amphoteric peptide-based fatliquor (APF) was prepared by introducing a flexible long chain into collagen polypeptide and compounding it with castor oil. The resulting amphiphilic amphoteric peptide-based structure of the APF ensured it had good compatibility with chrome-free tanning systems. In terms of the properties of the chrome-free tanned leather, the softness = 7.88 ± 0.21 mm, air permeability = (2.19 ± 0.04) × 103 mL·(cm−2·h−1), the burst height = 13.32 ± 2.22 mm, and tear strength = 17.77 ± 4.22 N·mm−1, with its overall performance, were comparable with that of chrome tanned leather. Furthermore, the absorption of the fatliquor and the dye increased to 89.68% ± 0.99% and 92.82% ± 0.93%, respectively, while the APF demonstrated excellent environmental friendliness, meaning the hazardous chemicals used in the leather fabrication process and discharged into the environment would be significantly reduced. This work is of great significance in terms of improving organic chrome-free ecological tanning systems and further promoting cleaner production within the leather industry.

Hyperbranched polymers, an innovative class of nano-polymers, could enhance the properties of fibers owning to their unique structures. In this study, the ester compound (HPAE) of 3-(bis(2-hydroxyethyl)amino)propionic acid and pentaerythritol was treated with undecylenic acid to obtain novel hyperbranched multiterminal alkenyl polymers (HPAE-UAs). The sizes of the HPAE-UAs could be controlled conveniently from 400 to 1300 nm by adjusting the capped fraction of the hydroxyl groups with undecylenic acids. The molecular structures of HPAE-UAs were characterized by means of FT-IR and 1H-NMR. Then, the effect of the HPAE-UAs on the structures, thermal, and mechanical properties of the wet blue leather were investigated. TEM and SEM demonstrated that the spacing between fibers was enlarged. The thermogravimetric analysis showed that the residual volume of leather could reach up to 30.3 % at about 500 °C. Furthermore, the shrinkage temperature increased to 89.4 °C. It was found that the HPAE-UAs used in leather could improve the thermal performance, physical and mechanical properties. All of these results indicate that HPAE-UAs can be used as a fatliquor with retanning in leather process.

In this work, the crystallization and polymorphic behavior of biodegradable poly(butylene adipate) in its composites with nylon-6 fabric were investigated. It was found that the nylon-6 fiber exhibits high nucleation ability toward the PBA as demonstrated by the increased crystallization temperature and the formation of transcrystalline layers. It was demonstrated that the nylon-6 induces the crystallization of PBA in its α-form under all of the used crystallization conditions. The effect of nylon-6 on the α-PBA crystallization was confirmed to be limited within a range of ca. 1 μm.

The superfine fiber synthetic leather base (SFSLB) is composed of the two components of nylon fibers and polyurethane. SFSLB has excellent performance, especially in terms of mechanical properties. However, compared with native leather, SFSLB has a hot feeling due to its poor moisture absorbent and transfer abilities. So our study proposed a method of grafting collagen-chrome tannins (C-CrT) on nylon fiber in the SFSLB for improving the moisture absorbent and transfer abilities. A three-step surface modification was developed, involving washing pretreatment, sulfuric acid hydrolysis and grafting of C-CrT on SFSLB. The dosage of sulfuric acid and chrome tannins, bath ratio, reaction temperature and the time for collagen permeation and chrome tannin cross-linking were optimized via single-factor experiments. Their efficiency was determined by measuring static water-vapor transmission rate (SWVT) and liquid wicking rate. The results showed that the dosage of sulfuric acid was 15% and chrome tannins was 5%, the bath ratio was 1500%, the reaction temperature was 60℃ and the time for collagen permeation and chrome tannin cross-linking was 3 hours. Under this condition, the SWVT of modified SFSLB was 986 g/m2 · 24 h, and the liquid wicking rate was 1.323 mm/s. Compared with untreated SFSLB, the SWVT and liquid wicking rate of modified SFSLB were improved by 90.35% and 344%, respectively. The static state contact angle, scanning electron microscopy and X-ray photoelectron spectroscopy were used for the determination of sample surface performance, morphology and chemical composition, and states before and after treatment, respectively.

In this paper, we found that silver ions can efficiently degrade xanthene-based fluorescent dyes during the formation of Ag/AgCl nanoparticles under photo-assisted action. The experimental results indicates that both the ultraviolet absorption peak and fluorescence peak of xanthene-based fluorescent dyes disappeared in the presence of silver ions when the solution was irradiated with blue-violet light, implying the efficient degradation of these fluorescent dyes. Transmission electron microscopy (TEM) and Dynamic light scattering (DLS) analysis suggested the formation of nanoparticles during this process. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and STEM-mapping confirmed that the main chemical component of the nanoparticles was Ag/AgCl. To the best of our knowledge, it was the first time that the photo-assisted formation process of Ag/AgCl nanoparticles has been applied for the degradation of xanthene-based fluorescent dyes in a wide pH range (2.0–11.0) despite that Ag/AgCl nanoparticles are also widely used in dye degradation, and our experimental results also showed that the formation of photo-assisted Ag/AgCl nanoparticles is more efficient than Ag/AgCl nanoparticles themselves in dye degradation.

The microfiber synthetic leather base pretreated by sulfuric acid was modified by collagen in which the organic phosphine FP was used as a cross-linking agent, for the purpose of increasing the active groups and improving its properties. Compared with the pretreated base, it was found that the amino content in the modified base was two times and the carboxyl content was three times. The water vapor permeability of the modified base increased by 65% and the moisture absorption increased by 181%. It was further found that the tensile strength of the modified base was 19.06 N/mm2, the elongation at break was 54% and the tear strength was 112.34 N/mm. The test results of Fourier transform infrared spectroscopy, scanning electron microscopy, atomic force microscopy, thermogravimetric analysis and water contact angle showed that the collagen molecules had evenly cross-linked with fiber. The modified base microfiber dispersion was greatly increased, the hydrophility was enhanced and the relative average roughness was decreased. Moreover, modification by collagen also affected the thermal properties of the base.

Two kinds of insoluble collagen fiber (CF) were prepared by grafting amino- and carboxyl-terminated hyperbranched polyamide into collagen fiber using the cross-linking and terminal groups modification methods: (1) grafting amino terminated hyperbranched polyamide to CF by glutaraldehyde, and (2) condensation of the resulting carboxyl with glyoxylic acid. Their structures were characterized by FT-IR, SEM-EDX, ion distribution, and XRD. Because of the condensation of glyoxylic acid, the adsorption peaks of carboxyl groups occurred at 1,740 cm−1 in the FTIR spectra. The adsorption capabilities of the products for Cr(III) were studied by batch experiments. The pseudo-first-order, pseudo-second-order, and intra-particle diffusion model equations were used for the kinetic studies. The results showed that the products exhibited better adsorption capabilities for Cr(III). The adsorption capability of carboxyl-terminated product was higher than that of amino-terminated one and this is attributed to the carboxylic functional groups in the carboxyl-terminated product, which are responsible for their cationic ion exchange phenomenon. It was also observed that kinetic data correspond very well to the pseudo-second-order equation.

The effects of crystallization temperature and blend ratio on the polymorphic crystal structures of poly(butylene adipate) (PBA) in poly(butylene succinate) (PBS)/poly(butylene adipate) (PBS/PBA) blends were studied by means of differential scanning calorimetry (DSC), wide-angle X-ray diffraction (XRD) and atomic force microscopy (AFM). It was revealed that the polymorphism of PBA can be regulated by the blend ratio even in a non-isothermal crystallization process. The results demonstrate that high temperature favors flat-on α crystals, while low temperature contributes to edge-on β crystals. It was also found that the effect of blend ratio on the crystallization mechanism of PBA is well coincident with that of the crystallization temperature. The increment of PBS content in the PBS/PBA blend gives rise to more β-form crystals of PBA. For those PBS/PBA blends with low PBA content, the interlamellar phase segregation of PBA makes its molecular chains so difficult to diffuse from one isolated microdomain to another that high crystallization temperature and sufficiently long crystallization time will be required if the PBA α-type crystals are targeted.

The isocyanate-terminated polyurethane pre-polymer (PPU) was synthesized via the step-growth polymerization approach by using polycarbonate diol (PCDL, Mn = 2000) and isophorone disocyanate (IPDI) as monomers, dibutyltin dilaurate (DBTDL) as the catalyst. Subsequently, the hyperbranched polyurethane (HBPU) was synthesized by graft copolymerization using PPU, hyperbranched poly(amide–ester) polyol (HPAE) and 1,4-butanediol (BDO). The molecular structure of HBPU was characterized by means of FTIR, 1H-NMR, and 13C-NMR. It was observed that HBPU was synthesized as anticipated. The thermal and mechanical properties, the microstructure, and morphologies of the filmed HBPU and LPU (linear polyurethane) were tested, respectively. The filmed HBPU, revealed better thermal stability, and higher Tg accompanied with lower viscosity than those of filmed LPU. Additionally, the mechanical experiment showed that the filmed HBPU exhibited enhanced mechanical properties because it contained certain amounts of HPAE. Compared with its linear analog (LPU) specimen, the tensile strength of the filmed HBPU containing 10 wt % HPAE increased by 1.9 times (up to 28.15 MPa), and its elongation at break increased by 1.5 times (up to 543.8%), resulting from the dual effects of the hydrogen bonding and the crosslinking density in the HBPU system. The morphologies of filmed HBPU were characterized by means of WAXD and SEM, which indicated that increasing the content of HPAE lowers the crystallinity of HBPU. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2671–2679, 2013

The isocyanate-terminated linear polyurethane prepolymer (LPPU) was successfully synthesized via step-by-step polymerization, with isophorone disocyanate (IPDI) and polytetramethylene ether glycol (PTMG, Mn = 2000 g/mol) used as raw materials, dibutyltin dilaurate (DBTDL) as the catalyst, 1,4-butanediol (BDO) as the chain extender and anhydrous ethanol (EtOH) as the blocking agent. Then the hyperbranched poly (urethane-urea) (HBPU) containing amino groups was synthesized by grafting LPPU on amino-terminated hyperbranched polymers (NH2-HBP). The molecular structure of LPPU and HBPU were characterized by means of FT-IR and 1H-NMR. It was founded that LPPU and HBPU were successfully synthesized as anticipated. The thermal stability and crystalline morphology of LPPU and HBPU were characterized and analyzed by TG and XRD. Additionally, it was also found that, after addition of 10% HBPU, the water absorption rate, water vapor transmission rate, and water vapor permeability increased markedly by 162.02%, 400.00%, 260.00%, respectively. The tensile strength of membrane decreased by 24.57% and the elongation at break increased by 26.92%. Compared with the leather finished by commercial PU finishing agent, the leather finished by HBPU presented better properties. The water vapor permeability of the leather finished by increased by 13.0%, and the dry- and wet-rub resistances and the physical and mechanical performances were excellent. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44139.

The effects of the crystallization temperatures of poly(ethylene succinate) (PES) on the crystallization behavior of poly(ethylene oxide) (PEO) in their blends were investigated by means of differential scanning calorimetry, atomic force microscopy, and laser confocal fluorescent microscopy. It was found that confined and fractional crystallization of PEO takes place in the PES/PEO blends at all blend ratios if PES is crystallized at higher crystallization temperatures. And morphological observation gives a direct evidence of the different location distribution of PEO, resulting in the confined and fractional crystallization behavior.

Collagen extracted from leather waste was modified with maleic anhydride. Then, using ammonium persulfate as an initiator, by pre-modifying collagen reacted with styrene and ethyl acrylate monomers, a vinyl-grafted collagen sizing agent (VGCSA) for paper was prepared. Before the experiment, the performance of VGCSA was tested and VGCSA emulsion was applied to the surface sizing of the corrugated paper. Effects of the amount of VGCSA, the compound proportion of VGCSA, and starch and styrene-acrylic emulsion were studied relative to paper properties. The morphological changes of the paper before and after sizing were characterized by SEM. It was found that the collagen reacted with styrene and ethyl acrylate monomers. Through the grafting of vinyl and collagen, the crystallinity and thermal stability of VGCSA increased. The structure of VGCSA was spherical with a uniform size, and the average particle size was approximately 350 to 400 nm. After being sized, the surface fibers of paper became smooth and orderly. The optimal sizing of VGCSA was 8 g/m2. The optimal proportion of VGCSA with starch was 4:6, and the optimal proportion of VGCSA with SAE was 2:8. The research indicates that collagen extracted from leather waste could be used as a biomaterial, and environmental and economic benefits could be created as well.

A series of conjugated rigid-rod polymers, poly(p-phenylene benzobisoxazole) (PBO), poly(benzobisoxazole-2,6-diylvinylene) (PBOV), poly(benzobisoxazole-2,6-diyldivinylene) (PBODV) have been synthesized. UV absorption spectroscopy has been used to investigate the optical properties of these polymers in methanesulfonic acid (MSA) or in films. The results show that the introduction of vinyl segments into the poly(benzobisoxazole)s backbone narrowed the optical bandgap of this class of polymers. The UV spectra of the polybenzoxazole can be well predicted with the polybenzoxazole models by the semiempirical method AM1/ZINDO (Austin Method 1/Zerner's intermediate neglect of differential overlap), coupled to single configuration interaction. The UV spectra of polymers in MSA solution were red-shifted from that of the thin films and the theoretical UV spectra. The AM1/ZINDO-CI calculations of protonated PBO at N heteroatom suggest that the red shift is due to the protonation effect.

A new conjugated polymer poly(benzobisoxazole-2,6-diylvinylene) (PBOV) has been synthesized as an analogue of poly(p-phenylene benzobisoxazole) (PBO). The comparison between PBOV and PBO has been carried out by Fourier transform infrared spectroscopy, thermogravimetric analysis, UV, and photoluminescence (PL) spectroscopy. The UV absorption peaks, PL excitation and emission wavelengths of PBOV have a significant red-shift due to the better electronic delocalization. Similar to PBO, it can be observed in the PL spectra of PBOV at various concentrations in methanesulfonic acid (MSA) that the intensity of emission was depressed and the highly structured emission spectra gradually changed to featureless, red-shifted, and broad spectra with increasing concentration. The change in emission spectra can be attributed to the existence of the interchain aggregates, although PBOV does not show highly ordered structure as PBO does.

New rod−coil copolymers based on poly(p-phenylene benzobisoxazole) (PBO) have been synthesized and characterized to explore a new ordered molecular structure at the supramolecular level for regulating photophysical properties and obtaining new blue light-emitting materials. The microstructure and physical properties of such rod−coil copolymers, poly(1,4-phenylenebenzobisoxazole-co-octamethylenebenzobisoxazole) (PBO−PBOC8), were determined by FTIR, 1H NMR, viscometry, WAXD, and TGA. The chain flexibility and photophysical properties of copolymers can be efficiently modulated by the copolymer composition while the structure remains ordered, which is quite different from their analogue: the amorphous rod−coil copolymers poly(1,4-phenylenebenzobisthiazole-co-decamethylenebenzobisthiazole) (PBZT−PBTC10) reported by Jenekhe et al. [J. Am. Chem. Soc. 1995, 117, 7389]. Photophysical properties of these polymers both in methanesulfonic acid (MSA) and in the solid state were investigated in detail using UV absorpt...

A new conjugated rigid-rod polymer, poly(benzobisoxazole divinylene) (PBODV) has been synthesized and characterized using FTIR, 1H NMR, viscometry, wide-angle X-ray diffraction, and thermogravimetric analysis. UV absorption spectroscopy and photoluminescence spectroscopy were also used to investigate the photophysical properties of these polymers in methanesulfonic acid in detail. The results show that the introduction of trans-vinylene segments into the poly(benzobisoxozale)s backbone narrowed the optical bandgap of this class of polymers. The excitation and emission spectra change significantly with the concentration both in shape and the peak positions, indicating the formation of aggregates in solution. Furthermore, electronic paramagnetic resonance studies show the intrinsic paramagnetic defects in the PBODV, which can be interpreted using a soliton–antisoliton model.