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1.
Heliyon ; 10(12): e31846, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-38952363

ABSTRACT

The Internet of Things communication protocol is prone to security vulnerabilities when facing increasing types and scales of network attacks, which can affect the communication security of the Internet of Things. It is crucial to effectively detect these vulnerabilities in order to improve the security of IoT communication protocols and promptly fix them. Therefore, this study proposes a distributed IoT communication protocol vulnerability detection method based on an improved parallelized fuzzy testing algorithm. Firstly, based on design principles and by comparing different communication protocols, a communication architecture for the distribution network's Internet of Things was constructed, and the communication protocols were formalized and decomposed. Next, preprocess the vulnerability detection samples, and then use genetic algorithm to improve the parallelized fuzzy testing algorithm to perform vulnerability detection. Through this improved algorithm, the missed detection rate and false detection rate can be effectively reduced, thereby improving the security of IoT communication protocols. The experimental results show that the highest missed detection rate of this method is only 4.0 %, and the false detection rate is low, with high detection efficiency. This indicates that the method has good performance and reliability in detecting vulnerabilities in IoT communication protocols.

2.
Dalton Trans ; 53(10): 4492-4500, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38348738

ABSTRACT

As important building blocks in natural products and organic synthesis, thioethers have a wide range of potential applications. Herein, polyoxometalate-based ionic liquids (POM-ILs-SO3H) derived from N-alkyl imidazole were synthesized and used for the first time for the thiolation of alcohols to construct C-S bonds in a series of benzyl thioethers. This type of POM-ILs-SO3H catalyst exhibited high catalytic activity, providing up to 98% yield of thioether within 1 h at 70 °C. The alkyl chain length of the imidazole had a certain effect on the solubility of the POM-ILs-SO3H catalysts in the reaction solvent, and then affected their catalytic activity. The catalytic system had a wide substrate scope and was suitable for the reaction of tertiary and secondary benzyl alcohols with thiophenols or cycloalkyl thiols. In particular, [PIMPS]3PW12O40 (PIM = 1-propylimidazole, PS = propane sulfonate) as a reversible phase transformation-type catalyst, combining the advantages of homogeneous and heterogeneous catalysts, exhibited high activity and good recyclability with only a slight decrease in the yield after five runs. Additionally, a carbocation mechanism was proposed for the thiolation reaction of alcohols.

3.
Dalton Trans ; 52(36): 12582-12596, 2023 Sep 19.
Article in English | MEDLINE | ID: mdl-37646095

ABSTRACT

Polyoxovanadates (POVs) have received widespread attention in catalytic applications due to their various structures and remarkable redox properties. By introducing a second transition metal, POV-based inorganic-organic hybrid (POVH) catalysts show increasing stability and more catalytic active sites compared with pure POVs. In this perspective article, POVH materials as oxidative catalysts have been classified into two main categories according to the interactions between transition metal-complex units and POV clusters: (i) hybrids with metal-organic units act as isolated cations and (ii) hybrids with an organic ligand coordinate to the second transition metal, which is further linked to a POV cluster via oxygen bridges directly or indirectly to give zero-, one-, two- or three-dimensional supramolecular structures. The oxidative conversion of organic compounds, including thiophene derivatives, thioethers, alkanes, alcohols, and alkenes, and oxidative detoxification of a sulfur mustard simulant or degradation of lignin, along with the oxidative photo/electrocatalytic transformation of organic compounds catalyzed by POVH materials, are discussed in detail. Furthermore, the challenges and prospects toward the development of POVH catalysts are explored briefly from our perspectives.

4.
RSC Adv ; 12(41): 26945-26952, 2022 Sep 16.
Article in English | MEDLINE | ID: mdl-36320831

ABSTRACT

In this work, a luminescent metal-organic framework (Eu-MOF {[Eu6L6(µ3-OH)8(H2O)3]8·H2O} n ) was constructed by a solvothermal method with a linear organic ligand L (10-[(2-amino-4-carboxyl-phenyl)ethynyl]anthracene-9-carboxylic acid) based on anthracene and alkyne groups and using Eu3+ as the metal center. The MOF exhibits a stable UiO-66 crystal structure, and a six-core cluster twelve-linked secondary structural unit was successfully synthesized using 2-fluorobenzoic acid as a modulator, forming a classical fcu topology. Moreover, it exhibits good chemical stability. Interestingly, Eu-MOF exhibited high selectivity and sensitive fluorescence burst properties towards Fe3+ ions and 2,4,6-trinitrophenol (TNP) in DMF solution. For Fe3+, the K SV value is 5.06 × 105 M-1 and the LOD value is 5.1 × 10-7 M. For TNP, the K SV value is 1.92 × 104 M-1 and the LOD value is 1.93 × 10-6 M. In addition, Eu-MOF showed good anti-interference ability and fast response. This work provides an excellent fluorescent sensor for the detection of Fe3+ and 2,4,6-trinitrophenol (TNP) residues in contaminants.

5.
Bioelectrochemistry ; 145: 108073, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35189559

ABSTRACT

Accurate detection of disease markers in a complex biological media is a major challenge because of serious biofouling and non-specific protein adsorption. Herein, a universal strategy for sensitive and low-fouling detection of thrombin in human serum was developed based on hyaluronic acid functionalized polydopamine. The material hyaluronic acid with hydroxyl groups was grafted to the polydopamine modified electrode surface through the connection of 6-mercapto-1-hexanol to exert antifouling performance, and the hyaluronic acid also provided a good substrate for the immobilization of aptamers specific for thrombin. The constructed aptasensor showed good sensitivity and selectivity toward the detection of thrombin with a detection limit as low as 0.03 pM. Moreover, thanks to the presence of hyaluronic acid within the sensing interface, the aptasensor was able to assay thrombin in diluted human serum with markedly decreased side effect of non-specific adsorption.


Subject(s)
Aptamers, Nucleotide , Biofouling , Biosensing Techniques , Hyaluronic Acid , Thrombin , Biofouling/prevention & control , Electrochemical Techniques , Humans , Hyaluronic Acid/chemistry , Indoles/chemistry , Limit of Detection , Polymers/chemistry , Thrombin/analysis
6.
Dalton Trans ; 50(29): 10082-10091, 2021 Jul 27.
Article in English | MEDLINE | ID: mdl-34213516

ABSTRACT

By introducing 4-amino-1,2,4-triazole (4-NH2-trz), three new polyoxovanadate-based metal-organic frameworks (PMOFs) [Ni3(4-NH2-trz)6][V6O18]·3H2O (1), [Co3(4-NH2-trz)6][V6O18]·3H2O (2) and [Cu3OH(4-NH2-trz)3H2O][VO3]5·H2O (3) have been synthesized and thoroughly characterized by single-crystal X-ray diffraction (SXRD), powder X-ray diffraction (PXRD), infrared spectroscopy (FT-IR), thermogravimetric (TG) analysis and elemental analysis (EA). Among them, PMOFs 1 and 2 had similar structures containing [V6O18]6- clusters; however, PMOF 3 was isolated as a structure containing a [VO3]55- cluster when the amount of the 4-NH2-trz ligand was reduced to half with the other synthesis conditions being the same as those of PMOFs 1 and 2 except for the transition-metal chlorides. Furthermore, the negative charges of polyoxovanadate [V6O18]6- and [VO3]55- anions were balanced by trinuclear complex cations [Ni3(4-NH2-trz)6]6- for 1, [Co3(4-NH2-trz)6]6- for 2 and [Cu3OH(4-NH2-trz)3H2O]5- for 3, respectively. PMOFs 1-3 were further used as heterogeneous catalysts in the Knoevenagel condensation under solvent-free conditions and showed high catalytic activity. PMOF 1 showed moderate catalytic activities in the oxidation of various aromatic alcohols using H2O2 as an oxidant. Moreover, PMOF 1 could be reused at least three times without losing its activity.

7.
Dalton Trans ; 49(40): 14148-14157, 2020 Oct 28.
Article in English | MEDLINE | ID: mdl-33021293

ABSTRACT

By rationally controlling hydrothermal conditions, three new inorganic-organic hybrid polyoxovanadates (POVs) [Ni2(1-vIM)7H2O][V4O12]·H2O (1), [Cu2(1-vIM)8][V4O12]·H2O (2) and [Co(1-vIM)H2O][VO3]2 (3) (1-vIM = 1-vinylimidazole) have been synthesized and thoroughly characterized by single X-ray diffraction (SXRD), powder X-ray diffraction (PXRD), infrared spectroscopy (FT-IR), and elemental analyses (EA). Interestingly, complexes 1 and 2 have similar structures including [V4O12]4- clusters; complex 3, however, was isolated as a structure by including the [VO3]22- cluster under a different synthetic condition compared with those of 1 and 2. Both complexes 1 and 2 display an interesting 3D supramolecular structure, and complex 3 shows a 2D two parallel networks supramolecular structure linked by a [Co2O2] unit due to the different coordination environments of the central metals. Three inorganic-organic hybrid POVs as heterogeneous catalysts are active in the selective oxidation of sulfides to produce sulfoxides or sulfones with high conversion and high selectivity (up to 99.5% for sulfoxides and 98.5% for sulfones respectively catalyzed by 1). Complex 1 is also used as catalyst in the oxidative CEES (2-chloroethyl ethyl sulfide, a sulfur mustard simulant) abatement with high activity and selectivity toward the corresponding sulfoxide. Moreover, complex 1 can be reused at least three times in sulfoxidation reactions without losing its activity.

8.
Biosens Bioelectron ; 164: 112317, 2020 Sep 15.
Article in English | MEDLINE | ID: mdl-32479342

ABSTRACT

An antifouling electrochemical biosensing platform was constructed based on conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) planted with designed peptides. The designed peptides containing doping and antifouling sequences were anchored to an electrode surface, followed by the electrochemical polymerization of PEDOT. The negatively charged doping sequence of the peptide was gradually doped into the PEDOT during the polymerization process, and by controlling the polymerization time, it was able to exactly dope the whole doping sequence into the PEDOT film, leaving the antifouling sequence of the peptide stretched out of the PEDOT surface. Therefore, an excellent conducting and antifouling platform was constructed just like planting a peptide tree in the PEDOT soil. With antibodies immobilized on the peptide, an antifouling electrochemical biosensor for the detection of a typical biomarker CA15-3 was developed. Owing to the unique properties of the conducting polymer PEDOT and the antifouling peptide, the electrochemical biosensor exhibited high sensitivity and long-term stability, and it was capable of detecting CA15-3 in serum of breast cancer patients without suffering from biofouling. The strategy of planting designed antifouling peptides in conducting polymers offered an effective way to develop electrochemical sensors for practical biomarkers assaying in complex biological samples.


Subject(s)
Biosensing Techniques , Doping in Sports , Peptides , Biomarkers , Bridged Bicyclo Compounds, Heterocyclic , Electrochemical Techniques , Humans , Peptides/blood , Polymers
9.
Anal Chem ; 92(10): 7186-7193, 2020 05 19.
Article in English | MEDLINE | ID: mdl-32289219

ABSTRACT

An electrochemical sensing platform for biomarker detection in complex serum samples with unique long-term antifouling performance was constructed, based on newly designed multifunctional peptides containing anchoring, doping, linking, and antifouling sequences. The designed peptides were first attached onto an electrode surface with the assistance of the anchoring sequences, and the negatively charged doping sequences as dopants for conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) were then precisely doped into the electropolymerized PEDOT to form a conducting and stable substrate, leaving the linking and antifouling sequences exposed on the PEDOT substrate surface. The linking sequence of the peptide between the doping and antifouling parts was designed to be beneficial for enhancing the antifouling performance. After the biorecognizing probe immobilization, the obtained biosensor was able to detect targets with a low limit of detection of 2.3 fM and high specificity in complex biological fluids. More importantly, the electrochemical biosensor exhibited incomparable long-term antifouling performances over previous reports and retained their antifouling capabilities for 20 days, indicating a promising feasibility of this design strategy for the construction of biosensors and bioelectronics to be used or implanted in real biological systems.


Subject(s)
Biosensing Techniques , Electrochemical Techniques , MicroRNAs/blood , Peptides/chemistry , Biomarkers/blood , Electrodes , Humans , Peptides/chemical synthesis , Surface Properties
10.
RSC Adv ; 10(2): 784-789, 2020 Jan 02.
Article in English | MEDLINE | ID: mdl-35494449

ABSTRACT

Humic acid is a non toxic, inexpensive, easily available high-molecular weight polymer. A simple and facile one pot three-component synthesis of 5-substituted 1H-tetrazoles from aldehydes, hydroxyamine hydrochloride and sodium azide using humic acid as an efficient catalyst in water is described. The method reported has several advantages such as high to excellent yields, easy work-up, mild reaction conditions, use of water as a green solvent, and a commercially available, nontoxic and reusable catalyst.

11.
Spectrochim Acta A Mol Biomol Spectrosc ; 216: 328-334, 2019 Jun 05.
Article in English | MEDLINE | ID: mdl-30909089

ABSTRACT

Considering the excellent photochemical properties of ruthenium(II) complexes, two new ruthenium(II) complexes, RuL1-DNBS and RuL2-DNBS, have been developed as phosphorescence probes for detection of biothiols in 100:1 (v/v) Hepes buffer (20 mM, pH = 7.2)/CH3CN solution. The response rate was highly improved of these two probes toward biothiols because the steric interactions between 1H-imidazo [4, 5-f] [1,10] phenanthroline group and ortho-2, 4-dinitrobenzensulfonate resulted in a relatively rapid thiol-induced SNAr substitution reaction. RuL1-DNBS and RuL2-DNBS were weakly phosphorescent owing to the effectual photoinduced electron transfer from ruthenium(II) luminophore to the sensing group, 2,4-dinitrobenzenesulfonyl. After reacting with biothiols, the 2,4-dinitrobenzenesulfonyl group of RuL1-DNBS and RuL2-DNBS were cleavaged and the RuL1 and RuL2 were obtained. Meanwhile, the phosphorescence were "turn-on". Both of these two probes can detect biothiols sensitively and selectively under physiological conditions with submicromolar detection limits. Furthermore, application of RuL2-DNBS for detecting of intracellular biothiols has been successfully performed in living Glioma cells.


Subject(s)
Coordination Complexes/chemistry , Dinitrobenzenes/chemistry , Luminescent Agents/chemistry , Ruthenium/chemistry , Sulfhydryl Compounds/analysis , Cell Line, Tumor , Glioma/chemistry , Glioma/pathology , Humans , Luminescent Measurements/methods , Optical Imaging/methods , Phenanthrolines/chemistry
12.
Dalton Trans ; 48(8): 2569-2573, 2019 Feb 19.
Article in English | MEDLINE | ID: mdl-30720833

ABSTRACT

Highly selective detection of trace metal ions has become one of the most urgent issues in public security and living systems. Developing a highly efficient fluorescent sensor for manganese(ii) (Mn2+) ions is a huge challenge. Herein, by utilizing the solvent regulation approach, a pair of terbium metal-organic frameworks (UPC-36, [Tb2(btdc)3(DMF)(H2O)4]·DMF and UPC-37, [Tb2(btdc)3(H2O)6]) based on a π-electron-rich ligand (H2btdc = 2,2'-bithiophene-5,5'-dicarboxylic acid) has been chosen as highly efficient sensors for the selective detection of Mn2+ ions. Interestingly, the fluorescence of UPC-36 can be quenched by Mn2+, Cu2+, Al3+, Cr3+ and Fe3+ ions, while UPC-37 can only be quenched by Mn2+ ions. For detecting Mn2+ ions, the limit of detection (LOD) values are calculated to be 0.813 mM and 0.715 mM for UPC-36 and UPC-37 respectively. According to the ICP results, UPC-37 has stronger interactions with Mn2+ ions because of the more regular arrangement of ligands existing in UPC-37, so it exhibits a high sensitivity and selectivity (Ksv = 5.25 × 105 M-1).

13.
RSC Adv ; 9(15): 8239-8245, 2019 Mar 12.
Article in English | MEDLINE | ID: mdl-35518665

ABSTRACT

Porous organic polymers have attracted significant attention owing to their large specific surface area, excellent chemical and thermal stability, and controllable skeletons. phenanthroline-based microporous organic polymer (Phen-MOP) has been synthesized via a cost-effective method based on the Scholl reaction. The Phen-MOP polymer exhibits high surface area and good stability. Owing to the phenanthroline skeleton embedding into the microporous polymer framework, the Phen-MOP can serve as a platform to support a transition metal catalyst. After being post-modified with palladium acetate, the synthesized Phen-Pd-MOP framework can serve as a highly efficient heterogeneous catalyst for the Suzuki-Miyaura coupling reaction and the Heck coupling reaction. Moreover, the Phen-Pd-MOP catalyst could be reused at least 10-12 times without any significant loss of the catalytic activity.

14.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 1): o18, 2014 Jan 01.
Article in English | MEDLINE | ID: mdl-24526969

ABSTRACT

The title compound, C17H19NO3S, was synthesized from 4-benzhydryl-idene-amino-12-hy-droxy-[2.2]para-cyclo-phane and methane-sulfonyl chloride. In the mol-ecule, the distance between the centroids of two aromatic rings is 2.960 (5) Å. In the crystal, weak N-H⋯O and C-H⋯O hydrogen bonds link the mol-ecules into layers parallel to the ac plane.

15.
Inorg Chem ; 49(23): 10781-7, 2010 Dec 06.
Article in English | MEDLINE | ID: mdl-21028893

ABSTRACT

A series of 3-D lanthanide porous coordination polymers, [Ln(6)(BDC)(9)(DMF)(6)(H(2)O)(3)·3DMF](n) [Ln = La, 1; Ce, 2; Nd, 3], [Ln(2)(BDC)(3)(DMF)(2)(H(2)O)(2)](n) [Ln = Y, 4; Dy, 5; Eu, 6], [Ln(2)(ADB)(3)(DMSO)(4)·6DMSO·8H(2)O](n) [Ln = Ce, 7; Sm, 8; Eu, 9; Gd, 10], {[Ce(3)(ADB)(3)(HADB)(3)]·30DMSO·29H(2)O}(n) (11), and [Ce(2)(ADB)(3)(H(2)O)(3)](n) (12) (H(2)BDC = benzene-1,4-dicarboxylic acid and H(2)ADB = 4,4'-azodibenzoic acid), have been synthesized and characterized. In 1-3, the adjacent Ln(III) ions are intraconnected to form 1-D metal-carboxylate oxygen chain-shaped building units, [Ln(4)(CO(2))(12)](n), that constructed a 3-D framework with 4 × 7 Å rhombic channels. In 4-6, the dimeric Ln(III) ions are interlinked to yield scaffolds with 3-D interconnecting tunnels. Compounds 7-10 are all 3-D interpenetrating structures with the CaB6-type topology structure. Compound 11 is constructed by ADB spacers and trinulcear Ce nodes with a NaCl-type topology structure and a 1.9-nm open channel system. In 12, the adjacent Ce(III) ions are intraconnected to form 1-D metal-carboxylate oxygen chain-shaped building units, [Ln(4)(CO(2))(12)](n), and give rise to a 3-D framework. Moreover, 6 exhibits characteristic red luminescence properties of Eu(III) complexes. The magnetic susceptibilities, over a temperature range of 1.8-300 K, of 3, 6, and 7 have also been investigated; the results show paramagnetic properties.

16.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 11): m1431-2, 2010 Oct 23.
Article in English | MEDLINE | ID: mdl-21588856

ABSTRACT

In the title coordination polymer, {[Nd(C(5)H(2)N(3)O(6))(C(2)O(4))(H(2)O)(4)]·4H(2)O}(n), the oxalate dianions link adjacent nine-coordinate, tricapped trigonal-prismatic Nd(III) atoms into a chain running along the b axis. The 3,5-dinitropyridin-4-oxido N-oxide ligand is formally a zwitterionic anion; the anion binds to the metal atom through the N-oxide O atom. The chains are connected into a three-dimensional network by O-H⋯O hydrogen bonds involving the coordinated and uncoordinated water mol-ecules.

17.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 11): m1484, 2010 Oct 30.
Article in English | MEDLINE | ID: mdl-21588899

ABSTRACT

Two 3-nitro-phthalate dianions bridge two water-coordinated 2,2'-bipyridine-chelated Cu(II) atoms about a center of inversion to generate the title dinuclear compound, [Cu(2)(C(8)H(3)NO(6))(2)(C(10)H(8)N(2))(2)(H(2)O)(2)]·2H(2)O. The geometry of the Cu(II) atom is a distorted square pyramid. Adjacent mol-ecules are linked through the coordinated and solvent water mol-ecules to form a linear ribbon running along the a axis of the monoclinic unit cell.

18.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 11): m1448, 2009 Oct 28.
Article in English | MEDLINE | ID: mdl-21578177

ABSTRACT

In the planar (r.m.s. deviation = 0.027 Å) title compound, [Hg(C(7)H(5)O(2))Cl], the Hg(II) atom shows a typical linear coordination by a C atom of the benzene ring and a Cl atom. Inter-molecular O-H⋯O hydrogen bonds are present in the crystal structure, resulting in chains propagating along the b axis. The crystal studied was a non-merohedral twin, with a twin ratio of 0.802 (2):0.198 (2).

19.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 3): m354, 2009 Feb 28.
Article in English | MEDLINE | ID: mdl-21582116

ABSTRACT

The asymmetric unit of the title compound, {[Zn(C(7)H(7)O(2))(2)(C(10)H(8)N(2))]·4H(2)O}(n), contains a highly distorted octa-hedral Zn(II) metal center strongly coordinated by two N atoms of two 4,4'-bipyridine (4,4'-bipy) ligands and chelated by two 4-methyl-benzoate anions. The crystallographic inversion center and glide plane present at the center of the C-C single bond of 4,4'-bipy, along with the cis coordination motif of the 4,4'-bipy, lead to one-dimensional zigzag chains. There are a large number of water mol-ecules in the crystal structure, which also form one-dimensional chains through O-H⋯O hydrogen bonds.

20.
Dalton Trans ; (12): 1832-40, 2004 Jun 21.
Article in English | MEDLINE | ID: mdl-15381988

ABSTRACT

A series of diorganotin(IV) compounds of the type [R(2)Sn(pca)Cl](3)(R = CH(3); (n)Bu; C(6)H(5); C(6)H(5)CH(2); Hpca = 2-pyrazinecarboxylic acid), R(2)Sn(pca)(2)(mH(2)O)xnH(2)O (m= 1: R = CH(3), n= 2, R =(n)Bu, n= 0; m= 0, n= 0: R =(n)Bu, C(6)H(5), C(6)H(5)CH(2)) and (Et(3)NH)(+)[R(2)Sn(pca)(2)Cl](-)xmH(2)O (m= 0: R = CH(3), (n)Bu, C(6)H(5)CH(2); m= 1: R = C(6)H(5)) have been obtained by reactions of 2-pyrazinecarboxylic acid with diorganotin(iv) dichloride in the presence of sodium ethoxide or triethylamine. All compounds were characterized by elemental, IR and NMR spectra analyses. Except for compounds, and, the others were also characterized by X-ray crystallography diffraction analyses, which revealed that compounds and were trinuclear macrocyclic structures with six-coordinate tin(IV) atoms, compounds and were monomeric structures with seven-coordinate tin(IV) atoms, compounds and were polymeric chain structures with seven-coordinate tin(IV) atoms and compounds and were stannate with seven-coordinate tin(IV) atoms.

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