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In this paper, we consider the estimation algorithm of tensor response on vector covariate regression model. Based on projection theory of tensor and the idea of randomized algorithm for tensor decomposition, three new algorithms named SHOLRR, RHOLRR and RSHOLRR are proposed under the low‐rank Tucker decomposition and some theoretical analyses for two randomized algorithms are also provided. To explore the nonlinear relationship between tensor response and vector covariate, we develop the KRSHOLRR algorithm based on kernel trick and RSHOLRR algorithm. Our proposed algorithms can not only guarantee high estimation accuracy but also have the advantage of fast computing speed, especially for higher‐order tensor response. Through extensive synthesized data analyses and applications to two real datasets, we demonstrate the outperformance of our proposed algorithms over the stat‐of‐art. [ABSTRACT FROM AUTHOR]

Inspired by the definition of tensor-tensor product and tensor tubal rank, a randomized singular value decomposition of tensor is presented in this paper. Based on tensor singular value decomposition (t-SVD) and tensor randomized singular value decomposition (t-RSVD), we obtain two efficient algorithms to solve tensor completion problem. We also propose the adaptive rank method to adjust the tubal rank of tensor. The main advantage of the random projection-based t-RSVD is to cut down the computing time in consideration of large-scale problems. In the optimization process, the alternating minimization algorithm is employed to solve the tensor completion problem. Finally, numerical experiment results indicate that the t-RSVD is competitive and consumes less time than the t-SVD. The efficiency and feasibility of our methods are illustrated by the image and video recovery. [ABSTRACT FROM AUTHOR]

In this paper, we are concerned with a class of tensor equations. Some explicit solutions to these equations are obtained. They are extensions of some results given by Lancaster. At the end of the article, these results are also employed to prove Lyapunov and Stein stability theorems for tensors. [ABSTRACT FROM AUTHOR]

Tensor analysis has received enormous attention as the increasing prevalence of high-dimensional data in science research and engineering application. Tensor recovery is an important and meaningful problem for tensor analysis. It aims to complete a tensor from an observed subset of its entries disturbed by noise. However, classical methods either develop on the second-order statistics or Lasso-type penalty, leading to them not effectively dealing with gross or dense noise effectively. To address such issues, we propose a robust tensor recovery model for simultaneously completing a low tubal rank tensor with complex noise and missing data. Based on tensor–tensor product (t-product), we first develop a tensor factor Frobenius norm to exploit the low tubal rank property which is closely related to tensor nuclear norm and tubal rank. By utilizing the robust L 2 criterion, we derive the nonconvex objective function to accommodate the low tubal rank tensor. An implementable alternating minimization algorithm has been developed to estimate the low tubal rank tensor. It is worth noting that our method is able to jointly estimate the precision parameter to capture the hidden complex noise pattern. Furthermore, some convergence properties of the proposed algorithm are presented. A series of numerical experiments are conducted on both synthetic and real-world data to demonstrate the effectiveness and robustness of the proposed approach in comparison with the state-of-the-art methods. • A robust tensor recovery model is proposed for completing a low tubal rank tensor with complex noise and missing data. • Based on t-product, we develop a tensor factor Frobenius norm to exploit the low tubal rank property. • By utilizing the robust L 2 criteria, we derive the nonconvex objective function and obtain robust estimation algorithm. • Our method is able to jointly estimate the precision parameter to capture the hidden complex noise pattern. • The global convergence property is established for the nonconvex loss function. [ABSTRACT FROM AUTHOR]

This paper is concerned with the solution to the least squares problem for the quaternion Sylvester tensor equation. An iterative algorithm based on tensor format is presented to solve this problem. The convergence properties of the proposed iterative method are studied. We also consider the best approximate problem related to quaternion Sylvester tensor equation. Numerical examples are provided to confirm the theoretical results, which demonstrate that the proposed algorithm is effective and feasible for solving the least squares problem of the quaternion Sylvester tensor equation. [ABSTRACT FROM AUTHOR]

A series of substituted acetophenone oxime esters of Pyrithiobac were synthesized as potential herbicides. The structures of the synthesized new compounds were confirmed by 1H NMR, 13C NMR, HRMS, and X‐ray single‐crystal diffraction (XRD). The pre‐emergence and post‐emergence herbicidal activity studies show that 4‐CF3 (6 f), 4‐NO2 (6 i), 4‐NH2 (6 j), 4‐F (6 l), and 2,4‐2OCH3 (6 s) substituted acetophenone oxime esters of Pyrithiobac exhibit better pre‐emergence and post‐emergence herbicidal activities against monocotyledon and dicotyledon weeds than other synthesized new compounds. In pre‐emergence herbicidal activity study, 6 f, 6 i, 6 j, 6 l, and 6 s exhibit similar herbicidal activities against monocotyledon and dicotyledon weeds as compared to Staple (Pyrithiobac‐sodium). In post‐emergence herbicidal activity study, 6 f, 6 i, 6 j, 6 l, and 6 s exhibit similar herbicidal activities against dicotyledon weeds and better herbicidal activities against monocotyledon weeds as compared to Staple. Compounds 6 i and 6 l with high herbicidal activities and similar binding mode with acetolactate synthase as compared to Staple were further subjected to crop safety study. The results show that the safety of compound 6 l to cotton is as good as Staple and better than 6 i. The present work indicates that compound 6 l may serve as a new candidate for potential herbicides. [ABSTRACT FROM AUTHOR]

O‐(2,6‐bis(4,6‐dimethoxypyrimidin‐2‐yloxy)benzoyl)oxime 3‐trifluoromethylacetophenone (HB‐002) was synthesized as potential acetolactate synthetase (ALS)‐inhibiting herbicides. HB‐002 was characterized by 1H nuclear magnetic resonance (NMR), 13C NMR, high resolution mass spectrometer (HRMS), and X‐ray single‐crystal diffraction. The herbicidal activities of HB‐002 against four weeds were studied in greenhouse. The results show that the control effects of HB‐002 on Eclipta prostrata L. and Cyperus difformis are very weak. However, HB‐002 exhibits higher herbicidal activity against Leptochloa chinensis (L.) Nees than that of Pyribenzoxim. HB‐002 also shows certain control effect on Echinochloa oryzoides (Ard.) Flritsch. Molecular docking simulation was performed to study the binding affinity and probable binding modes of HB‐002 with ALS. In the binding mode, the trifluoromethyl group of HB‐002 forms two halogen bonds (fluorine) with ALS, contributing to the lower binding free energy of HB‐002 (‐45.336 kcal/mol) as compared to Pyribenzoxim (‐40.1286 kcal/mol) and m‐trifluoromethyl Pyribenzoxim (‐44.451 kcal/mol). The present work suggests that HB‐002 may serve as a new candidate for potential herbicides. [ABSTRACT FROM AUTHOR]

• The as-synthesized Fe-Mn binary oxides exhibited good activation. • HO and SO 4 − radicals were the dominant reactive oxygen species. • The strong synergistic interaction reactions occurred in the regeneration of Mn(II) and Fe(II). • The proportion of O in F 4.5 M 1 BO involved in the activation of the combined persulfate and hydrogen peroxide. Fe-Mn binary oxides (FMBOs) with different molar ratios of Fe and Mn (1:1–8:1) synthesized in a redox-precipitation method were investigated for the activation of a combination of persulfate (PS) and hydrogen peroxide (HP) for the degradation of 2,4-dinitrotoluene (2,4-DNT). X-ray diffraction and field-emission scanning electron microscopy were used to demonstrate FMBOs with different molar ratios exhibited no significant influence on crystallinity and morphology. The degradation efficiency and kinetics of 2,4-DNT in the FMBOs/PS/HP system were investigated. The results showed that F 4.5 M 1 BO exhibited better effectively heterogeneous catalytic activity in the activation of the combined PS and HP. The effects of initial HP and PS concentrations, F 4.5 M 1 BO dose, initial pH, and coexisting anions on the degradation efficiency and kinetics of 2,4-DNT were comprehensively investigated. A possible activation mechanism in the F 4.5 M 1 BO/PS/HP system was proposed based on electron paramagnetic resonance, radical scavenger tests, X-ray photoelectron spectroscopy, and Fourier transformation infrared spectroscopy. The results showed that Fe(II), Mn(II), and Mn(III) (is representative of the element in solid form) are active sites on the surface of F 4.5 M 1 BO that effectively activated the combined PS and HP to generate the dominant SO 4 − and HO. Furthermore, the proportions of lattice oxygen, surface adsorbed species, and adsorbed molecular water activated of the combined PS and HP. The strong synergistic interaction reaction among Fe(III), Mn(III), Mn(IV), and HP could be deduced and confirmed. These findings provide new insight into the potential of F 4.5 M 1 BO as a heterogeneous catalyst in the activation of the combined PS and HP for improving the degradation of refractory organic pollutants. [ABSTRACT FROM AUTHOR]

• CuFeS 2 exhibited a good performance for activated peroxymonocarbonate (APMC) process. • CuFeS 2 showed reversible redox properties and iron acted as catalytic active sites. • HCO 3 − rather than H 2 O 2 greatly influenced the performance of APMC process. • Al 2 O 3 -supported CuFeS 2 was effective and safe when used as fillers for APMC process. Recently, increasing attention has been paid to the activated peroxymonocarbonate (APMC) process, because it is envisioned to be engineered for the chemical oxidation remediation of groundwater in karstic regions with elevated levels of naturally occurring bicarbonate. In the present study, we explored the feasibility of using metal sulfides (CuFeS 2 , CuS, and FeS 2) as the catalysts for heterogeneous APMC (H-APMC) processes. Among the three synthesized metal sulfides, the CuFeS 2 catalyst exhibited reversible redox properties, thereby it had the best performance to activate peroxymonocarbonate (PMC) for the degradation of 2,4-dichlorophenol (2,4-DCP). The X-ray photoelectron spectroscopy analysis and density-functional-theory calculations both revealed that, for the CuFeS 2 -catalyzed APMC process, iron sites of CuFeS 2 acted as the catalytic active sites. Electron spin resonance and chemical quenching experiments revealed that the intermediated reactive species for a CuFeS 2 -catalyzed APMC process included hydroxyl radicals (OH), singlet oxygen (1O 2), superoxide radicals (O 2 −), and carbonate radicals (CO 3 −). It was also found that, under a low bicarbonate condition (≤25 mM), the concentration of H 2 O 2 was not the limiting factor that controlled the degradation rate of 2,4-DCP. Instead, bicarbonate concentration and catalyst dosage significantly influenced the performance of CuFeS 2 -catalyzed APMC process. Al 2 O 3 -supported CuFeS 2 catalyst (Al 2 O 3 @CuFeS 2) was prepared and tested as fillers for practical application. The flowing experiment using fixed-bed reactor showed that the Al 2 O 3 @CuFeS 2 fillers could effectively activate PMC and thereby degraded the 2,4-DCP. Runoff of the coated CuFeS 2 component occurred during the experiment, but the leached copper and iron species from the fillers were constantly at a low and safe level (<1.5 mg/L). The CuFeS 2 -catalyzed APMC process showed a good prospect for groundwater remediation in karstic regions. [ABSTRACT FROM AUTHOR]

We propose a class of iterative algorithms to solve some tensor equations via Einstein product. These algorithms use tensor computations with no matricizations involved. For any (special) initial tensor, a solution (the minimal Frobenius norm solution) of related problems can be obtained within finite iteration steps in the absence of roundoff errors. Numerical examples are provided to confirm the theoretical results, which demonstrate that this kind of iterative methods are effective and feasible for solving some tensor equations. [ABSTRACT FROM AUTHOR]

The biconjugate gradients (BiCG) and biconjugate residual (BiCR) methods are attractive ways for solving nonsymmetric linear system A x = b. In this paper, the BiCG and BiCR methods are extended to solve the high order Stein tensor equation. The convergent properties of the developed iterative algorithms are studied. Numerical examples are provided to confirm the theoretical results, which demonstrate that the proposed algorithms are effective and feasible for solving the Stein tensor equation. [ABSTRACT FROM AUTHOR]

This paper is devoted to the accuracy and stability of quaternion Gaussian elimination (qGE). First, considering the noncommutativity of quaternion multiplications, we establish the rules of quaternion floating-point operations. After that, roundoff error analyses of quaternion LU and qGE with partial pivoting (qGEPP) are presented to show the backward stability of qGEPP is affected by the growth factor. Then, the upper bounds for growth factors of qGE with partial or complete pivoting, and the quaternion matrices with maximal growth factor are investigated. Finally, growth factors of some special matrices are also studied, and the theoretical results are confirmed through several numerical experiments. A conjecture about the growth factor of quaternion Hadamard matrix is given. [ABSTRACT FROM AUTHOR]

• A doubly robust classification method is proposed by TRPCA and minimum distance criterion. • We apply the TRPCA of third-order tensor to the input by the low tubal rank with its tensor nuclear norm. • Our procedure is a data driven and adaptive supervised learning method. The growing prevalence of image data in engineering and medical applications motivates the need for classification performance that are robust against outliers. To facilitate efficient and data-driven classification and recovery method, in this paper, we propose a novel supervised learning strategy based on the robust principal component analysis for third-order tensor and minimum distance criterion L 2 E for logistic regression, which is named as doubly robust logistic regression. Our work applies the ADMM method to obtain updating algorithm, and its global convergence is established even though L 2 E loss function is non-convex. We also extend the estimation procedure to the case of incomplete observation in input matrix. The numerical experiments demonstrate the advantages of combining the logistic L 2 E with tensor robust principal component analysis which can not only increase the accuracy of classification but also improve the recovery accuracy of noisy image. Three real data analysis are further used to examine the outperformance of our proposed method over the stat-of-art. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we present a fast algorithm for solving Symmetric penta-diagonal systems. We give the feasibility and Stability analysis of the algorithm. Moreover, parallel computations can be implemented in the algorithm. The numerical examples verify the efficiency of the algorithm. [ABSTRACT FROM AUTHOR]

• Microplastics (MPs) affected soil physicochemical properties and enzyme activities. • Response sensitivities of bacteria and fungi to MPs were inconsistent. • Soil aggregates size governed the response sensitivities of bacteria and fungi to MPs. • MPs altered microbial community structures through the direct and indirect pathways. Microplastics (MPs) alter soil aggregation stability. However, studies have yet to determine whether these alterations further affect microbial community structures and diversities within different soil aggregates and whether they influence the responses of soil microbial structures and diversities to MPs in different aggregate fractions. In this study, long-term soil incubation experiments and soil fractionation were combined to investigate the effects of polyethylene microplastics (PE-MPs) on soil aggregate properties and microbial communities in soil aggregates with different particle sizes. Results showed that the existence of PE-MPs significantly reduced the physicochemical properties of soil aggregates, inhibited the activities of soil enzymes, and changed the richness and diversity of bacterial and fungal communities. Such variations exerted notable differences in soil aggregate levels. The response sensitivity of bacteria in the silt and clay fraction was higher than that in the macroaggregate fraction, but the response sensitivity of fungi in the macroaggregate fraction was higher than that in the silt and clay fraction. Relationships and path analysis between soil aggregate properties and microbial communities after PE-MPs addition were proposed. PE-MPs affected microbial community structures by directly and indirectly influencing soil microenvironmental conditions. The relative abundances of Acidobacteria , Gemmatimonadetes , Bacteroides , Basidiomycota , Chtridiomyota , and Glomeromycota were significantly correlated with physicochemical properties and soil enzyme activities. Enzyme activities were direct factors influencing soil microbial community structures, and physicochemical properties (i.e., dissolved organic carbon, soil available phosphorus) could indirectly affect these structures by acting on soil enzyme activities. Our findings helped improve our understanding of the responses of soil microbial structures and diversities to MPs through the perspective of different soil aggregates. [ABSTRACT FROM AUTHOR]

In this study, scrap irons (SI)/granular activated carbons (GAC) micro-electrolysis treatment and persulfate-releasing materials (PRM) treatment were employed to construct the combination reduction and oxidation system to treat 2,4-dinitrotoluene (2,4-DNT) contaminated groundwater. The 2,4-DNT treatment efficiencies in the PRM pre-treatment before SI/GAC micro-electrolysis treatment (FM-1 = PRM + SI/GAC) and SI/GAC micro-electrolysis pre-treatment before the PRM treatment (FM-3 = SI/GAC + PRM) were investigated in two separated columns. As control groups, the separated SI and GAC instead of the SI/GAC mixture were used in another two separated columns (FM-2 = PRM + SI + GAC; FM-4 = SI + GAC + PRM). The highest treatment efficiencies of 2,4-DNT in the FM-1 and FM-3 systems reached 79% and 93% during 5 PV, respectively. We found that the filling position of SI, GAC and PRM significantly affected the variations of pH, oxidation-reduction potential, Fe2+ and S 2 O 8 2− concentrations in the combined systems. These results indicated that the SI/GAC micro-electrolysis pre-treatment of 2,4-DNT before the PRM treatment (FM-3) is more beneficial. The fifteen main intermediates in the combined system were identified by the detection of liquid chromatograph mass spectrometer. Furthermore, the possible treatment pathways of 2.4-DNT were proposed on the basis of identified intermediates. The treatment mechanisms in the FM-1 and FM-3 systems were proposed with the reduction mechanism in the SI/GAC micro-electrolysis system and the oxidation mechanism in the PRM treatment. Therefore, the combination of the reduction pre-treatment with the SI/GAC micro-electrolysis system and the oxidation post-treatment with persulfate can effectively treat the nitroaromatic compounds contaminated groundwater. Unlabelled Image • The performances of the combination of reduction and oxidation treatment of 2,4-dinitrotoluene contaminated groundwater were investigated; • The scrap irons/granular activated carbons micro-electrolysis pre-treatment of 2,4-dinitrotoluene before persulfate treatment is more beneficial in the combined system; • The fifteen main intermediates in the combined systems were identified; • The reduction in the micro-electrolysis system and the oxidation in the persulfate treatment were the main treatment mechanism. [ABSTRACT FROM AUTHOR]

Little attention has been paid to the in situ -generated biogenic manganese oxides (BMnOx) for practical implementation in continuous groundwater remediation systems. The enrichment effects of manganese oxidizing bacteria (MOB) in bioaugmentation columns and the in situ -generated BMnOx for continuous thallium(I) (Tl(I)) removal from groundwater were investigated. Results indicated that Pseudomonas Putida MnB1 (strain MnB1) attached on the groundwater sediments (GS) can achieve a maximum of 97.37 % Mn(II) oxidation and generate 29.6 mg/L BMnOx, which was superior than that of traditional quartz sand (QS). The in situ -generated BMnOx in MOB_GS column effectively removed 10–100 μg/L Tl(I) under the interference of high concentrations of Fe(II) and Mn(II) in groundwater. Distinctive microbial enrichment effects occurred in the bioaugmentation columns under the competition of indigenous microbes in groundwater. The release of Mn(II) from the BMnOx inhibited with the decrease in Tl(I) removal efficiency. XAFS analysis revealed Tl(I) was effectively adsorbed by BMnOx and Mn-O octahedra with Tl-O tetrahedral coordination existed in BMnOx. This study provides an in-depth understanding of the in situ -generated BMnOx for the Tl(I) removal and contributes to the application of BMnOx in groundwater remediation. [Display omitted] • The enrichment effect of strain MnB1 in GS was better than that of traditional QS. • In situ-generated BMnOx achieved efficient and long-term Tl(I) removal from groundwater. • Specific microbial enrichment pattern occurred in the bioaugmentation columns. • The release of Mn(II) inhibited with the decrease in Tl removal efficiency. • Mn-O octahedra and Tl-O tetrahedral coordination relationships were found in BMnOx. [ABSTRACT FROM AUTHOR]

Natural attenuation (NA) is of great significance for the remediation of contaminated groundwater, and how to identify NA patterns of toluene in aquifers more quickly and effectively poses an urgent challenge. In this study, the NA of toluene in two typical soils was conducted by means of soil column experiment. Based on column experiments, dissolved organic matter (DOM) was rapidly identified using fluorescence spectroscopy, and the relationship between DOM and the NA of toluene was established through structural equation modeling analysis. The adsorption rates of toluene in clay and sandy soil were 39 % and 26 %, respectively. The adsorption capacity and total NA capacity of silty clay were large. The occurrence of fluorescence peaks of protein-like components and specific products indicated the occurrence of biodegradation. Arenimonas , Acidovorax and Brevundimonas were the main degrading bacteria identified in Column A, while Pseudomonas , Azotobacter and Mycobacterium were the main ones identified in Column B. The pH, ORP, and Fe(II) were the most important factors affecting the composition of microbial communities, which in turn affected the NA of toluene. These results provide a new way to quickly identify NA of toluene. [Display omitted] • DOM fluorescence fractions can quickly identify the toluene natural attenuation. • Moving window 2DCOS reveals variation of DOM during toluene natural attenuation. • The characteristics of DOM fluorescence indicate the functional microbial activity. • Biodegradation effect of toluene in sandy soil is higher than that in silty clay. • SEM quantified the effects of environmental factors on toluene degradation. [ABSTRACT FROM AUTHOR]

[Display omitted] • BMO with a final maturity of 91.25 % achieved 95.20 % Tl(I) (0.1 mg/L) removal. • Mn(III) intermediates and active EPS from MOB play important roles for Tl removal. • Reoxidation of Mn(II) to BMO can effectively enhance in situ Tl(I) removal. • Tl removal was controlled by hierarchical adsorption, oxidation and surface complexation. • BMO showed sound Tl(I) adsorption selectivity when multiple heavy metals coexisted. Little is known about the reciprocal effect of manganese-oxidizing bacteria (MOB), in situ-generated biogenic manganese oxide (BMO) and thallium (Tl) removal. In this study, the Tl(I) removal characteristics during extracellular BMO formation by Pseudomonas putida strain MnB1 were investigated. BMO with a final maturity of 91.25 % achieved 95.20 % Tl(I) removal during biogenic Mn(II) oxidation. The improvement mechanisms of Tl(I) removal in biological systems were mainly due to the involvement of Mn(III) intermediates and tyrosine and tryptophan protein-like substances from MOB. The addition of exogenous MOB reoxidized the residual Mn2+ to BMO, thus promoting Tl(I) removal. BMO showed a higher adsorption ability for Tl(I) at inner depths owing to its layer stacking structure, and 64.02 % Tl(I) was further oxidized to Tl(III) by highly matured BMO. Surface complexation also played an important role during Tl(I) removal. Moreover, BMO showed good adsorption selectivity for Tl(I) with coexisting Fe(III), Cr(III) and Cd(II). These findings expand existing knowledge on the characteristics of in situ-generated BMO and indicate that BMO has practical application value in Tl(I) decontamination from water. [ABSTRACT FROM AUTHOR]

Experimental scale and sampling precision are the main factors limiting the accuracy of migration and transformation assessments of complex petroleum-based contaminants in groundwater. In this study, a mesoscale indoor aquifer device with high environmental fidelity and monitoring accuracy was constructed, in which dissolved toluene and trichloroethylene were used as typical contaminants in a 1.5-year contaminant migration experiment. The process was divided into five stages, namely, pristine, injection, accumulation, decrease, and recovery, and characteristics such as differences in contaminant migration, the responsiveness of environmental factors, and changes in microbial communities were investigated. The results demonstrated that the mutual dissolution properties of the contaminants increased the spread of the plume and confirmed that toluene possessed greater mobility and natural attenuation than trichloroethylene. Attenuation of the contaminant plume proceeded through aerobic degradation, nitrate reduction, and sulfate reduction phases, accompanied by negative feedback from characteristic ion concentrations, dissolved oxygen content, the oxidation-reduction potential and microbial community structure of the groundwater. This research evaluated the migration and transformation characteristics of typical petroleum-based pollutants, revealed the response mechanism of the ecosystem to pollutant, provided a theoretical basis for predicting pollutant migration and formulating control strategies. [Display omitted] • Toluene and trichloroethylene properties lead to distinct fates in groundwater. • Pristine groundwater ecosystem exhibits high resistance to organic contamination. • The natural decay rate of toluene is 3.32-4.17 times that of trichloroethylene. • Physicochemical indicators are sensitive and responsive to contaminants. • The microbe-mediated transformation of contaminants is regulated by substrates. [ABSTRACT FROM AUTHOR]

A series of new trifluoromethyl‐substituted phenyl alkyl ketoxime esters of Bispyribac were synthesized as potential herbicides. All synthesized compounds were characterized by nuclear magnetic resonance (NMR) spectroscopy and high‐resolution mass spectrometry (HRMS). Sprout method and foliar spray method were used to study the herbicidal activity of the synthesized compounds. Among all synthesized compounds, compound 3 (4‐trifluoromethylphenyl n‐butyl ketoxime ester of Bispyribac) exhibits the highest herbicidal activity against Echinochloa crusgalli (L.) Beauv with median effect dose (ED50) of 1.7 μg/mL in pre‐emergence herbicidal activity study. The structure‐activity relationship analysis indicates that trifluoromethyl substitution on the phenyl group exhibits better activity than methoxy and methyl substitution on the phenyl group. The alkyl chain length also affects the activity significantly and the optimal alkyl chain length is four among the tested compounds. However, the substitution position of trifluoromethyl exhibits very limited influence on the activity. In post‐emergence herbicidal activity study, compound 3 (ED90 69.1056 g/hm2) exhibits better herbicidal activity against Echinochloa crusgalli (L.) Beauv than Pyribenzoxim (ED90 99.0810 g/hm2). Moreover, compound 3 exhibits better safety to hybrid rice variety II you 084 and rice variety Nanjing 44 than Pyribenzoxim in crop safety study. Compound 3 may serve as a lead compound for future herbicide discovery. [ABSTRACT FROM AUTHOR]

Paclitaxel (PTX) is a chemotherapeutic agent which shows antitumor activities against a broad spectrum of cancers. Yet, the current formulation of PTX used in clinic may cause a number of adverse reactions, which significantly limit its application. To obtain better clinical use of PTX, we report, for the first time, iRGD‐PTX conjugate nanoparticles (NPs) for targeted PTX delivery. iRGD‐PTX conjugate was synthesized from thiolated iRGD and 6‐maleimidocaproic acid‐PTX through Michael addition reaction. iRGD‐PTX NPs with hydrodynamic diameter of ~110 nm were self‐assembled from iRGD‐PTX conjugate in deionized water. The as‐prepared iRGD‐PTX NPs exhibit good stability in phosphate buffered saline (PBS) buffer and fetal bovine serum containing PBS buffer. iRGD‐PTX NPs exhibit sustained drug release behaviors. The in vitro studies show that iRGD‐PTX NPs can be internalized by 4T1 cells by integrin αV‐mediated endocytosis, resulting in better in vitro antitumor activity as compared to free PTX. The in vivo studies demonstrate that iRGD‐PTX NPs exhibit enhanced tumor accumulation. The iRGD‐PTX NPs reported here represent a novel PTX nanoplatform to achieve targeted PTX delivery. [ABSTRACT FROM AUTHOR]

The increasing risk of organic contamination of groundwater poses a serious threat to the environment and human health, causing an urgent need to develop long-lasting and adaptable remediation materials. Controlled-release materials (CRMs) are capable of encapsulating oxidants to achieve long-lasting release properties in aquifers and considered to be effective strategies in groundwater remediation. In this study, novel hydrogels (ASGs) with thermosensitive properties were prepared based on agarose and silica to achieve controlled persulfate (PS) release. By adjusting the composition ratio, the gelation time and internal pore structure of the hydrogels were regulated for groundwater application, which in turn affected the PS encapsulated amount and release properties. The hydrogels exhibited significant temperature responsiveness, with 6.8 times faster gelation rates and 2.8 times longer controlled release ability at 10 ℃ than at 30 ℃. The ASGs were further combined with zero-valent iron to achieve long-lasting degradation of the typical nitrobenzene compound 2,4-dinitrotoluene (2,4-DNT), and the degradation performance was maintained at 50 % within 14 PV, which was significantly improved compared with that of the PS/ZVI system. This study provided new concepts for the design of controlled-release materials and theoretical support for the remediation of organic contamination. [Display omitted] • ASGs achieve efficient loading and controlled release of persulfate. • Compared with previous CRMs, ASGs exhibit significant temperature responsiveness. • The gelation rate, pore structure and persulfate release are regulated by ASGs components. • Kinetic fitting confirms the complex Fickian diffusion of persulfate release. • ASGs/ZVI shows sustainable and effective degradation performance for 2,4-DNT. [ABSTRACT FROM AUTHOR]

High-precision displacement platforms are of great significance in micro/nanoscale manipulation, ultraprecision manufacturing, biological manipulation, and scanning probe microscopes. This paper presents a novel compliant planar parallelogram mechanism (CPPM) for high-precision translational motion utilizing 8 flexible initially curved beams (ICBs). Compared with the existing high-precision displacement platforms for traditional motion, CPPM combines the characteristics of large motion ranges, bidirectional anti-buckling and high load-bearing. Moreover, this new mechanism introduces more design parameters compared to traditional parallelogram mechanisms, thus generating other desired characteristics by optimizing these parameters. In this paper, a general mathematical model is first derived for quick design and model-based optimization, followed by nonlinear finite element method (FEM) validation. Three desired performance characteristics in compliant translational mechanisms are proposed thereafter to obtain three optimized designs through global optimization of the preset geometric parameters. Experimental results verify the accuracy of the mathematical model and demonstrate centimeter-level high-precision positioning within a large motion range. Finally, a comparative discussion of the anti-buckling mechanisms for translation is presented. • We present a compliant planar parallelogram mechanism with desired performances. • We use general tensural–compresural initially curved beams. • We develop and validate the mathematical model. • We optimize geometric parameters globally for three desired performance characteristics. [ABSTRACT FROM AUTHOR]

Mercury (Hg2+) contamination in water is associated with potential toxicity to human health and ecosystems. Many research studies have been ongoing to develop new materials for the remediation of Hg2+ pollution in water. In this study, a novel thiol- and amino-containing fibrous adsorbent was prepared by grafting 2-amino-5-mercapto-1,3,4-thiadiazol (AMTD) onto PAN fiber through a microwave-assisted method. The synthesized functional fiber was characterized by FTIR, SEM, and elemental analysis. Adsorption tests depicted that for mercury uptake, PAN MW -AMTD fiber exhibited enhanced adsorption capacity compared with other fibrous adsorbents and selective adsorption feature under the interference of other metal ions, including Pb2+, Cu2+, Cd2+, and Zn2+. The influence of pH on the adsorption process was investigated and the effect of temperature revealed that the adsorption sorption process was endothermic and the adsorption performance of PAN MW -AMTD was elevated with the increase of temperature. Kinetic studies of PAN MW -AMTD fiber followed the pseudo-second-order and the adsorption isotherm of Hg2+ was well fitted by Sips and Langmuir equations, given the maximum adsorption amount of 332.9 mg/g. XPS results suggested that a synergetic coordination effect of sulfur and nitrogen in functional fiber with mercury took responsibility for the adsorption mechanism in the uptake process. In addition, the prepared PAN MW -AMTD fiber could easily be regenerated with 0.1 M HCl for five times without significant reduction of mercury removal efficiency. Thus, this study will facilitate the research on novel functional material for the removal of mercury from water. • An AMTD-modified PAN fiber was efficiently prepared with MW-assisted method. • PAN MW -AMTD fiber displays excellent removal efficiency and selective ability for Hg2+. • Maximum adsorption capacity of PAN MW -AMTD fiber for mercury was obtained at 332.9 mg/g. • Adsorption mechanism is chemisorption and N and S coordinated with Hg2+. • PAN MW -AMTD fiber remained as a cost-effective and reusable chelating adsorbent. [ABSTRACT FROM AUTHOR]