Preliminary investigation on the causes of red tides in Qinhuangdao coastal areas in 2022.

To explore the causes of red tides in Qinhuangdao coastal water, we conducted surveys on both water quality and red tides during April to September of 2022 and analyzed the relationships between main environmental factors and red tide organisms through the factor analysis and canonical correspondence analysis. The results showed that there were eight red tides along the coast of Qinhuangdao in 2022, with a cumulative blooming area of 716.1 km2. The red tides could be divided into three kinds based on the major blooming organisms and occurrence time, Noctiluca scintillans bloom, diatom-euglena (Skeletonema costatum, Eutreptiella gymnastica, Pseudo-nitzschia spp.) bloom, and dinoflagellate (Scrippsiella trochoidea and Ceratium furca) bloom. Seasonal factor played roles mainly during July to September, while inorganic nutrients including nitrogen and phosphorus influenced the blooms mainly in April and July. The canonical correspondence analysis suggested that N. scintillans preferred low temperature, and often bloomed with high concentrations of ammonium nitrogen and dissolved inorganic phosphorus. S. costatum, E. gymnastica, and Pseudo-nitzschia spp. could tolerate broad ranges of various environmental factors, but favored high temperature and nitrogen-rich seawater. C. furca and S. trochoidea had higher survival rate and competitiveness in phosphate-poor waters. Combined the results from both analyses, we concluded that the causes for the three kinds of red tide processes in Qinhuangdao coastal areas in 2022 were different. Adequate diet algae and appropriate water temperature were important factors triggering and maintaining the N. scintillans bloom. Suitable temperature, salinity and eutrophication were the main reasons for the diatom-euglena bloom. The abundant nutrients and seawater disturbance promoted the germination of S. trochoidea cysts, while phosphorus limitation caused the blooming organism switched to C. furca and maintained the bloom hereafter.

Large-scale research on durability test cycle of fuel cell system based on CATC.

Durability is one of the technical bottlenecks restricting fuel cell electric vehicle development. As a result, significant time and resources have been invested in research related to this area worldwide. Current durability research mainly focuses on the single cell and stack levels, which is quite different from the usage scenarios of actual vehicles. There is almost no research on developing durability test cycles on the fuel cell system level. This paper proposes a universal model for developing a durability test cycle for fuel cell system based on the China automotive test cycle. Large-scale comparison tests of the fuel cell systems are conducted. After 1000 h test, the output performance degradation of three mass-produced fuel cell system is 14.49%, 9.59%, and 4.21%, respectively. The test results show that the durability test cycle proposed in this paper can effectively accelerate the durability test of the fuel cell system and evaluate the durability performance of the fuel cell system. Moreover, the methodology proposed in this paper could be used in any other test cycles such as NEDC (New European Driving Cycle), WLTC (Worldwide Harmonized Light Vehicles Test Procedure), etc. And it has comprehensive application value and are significant for reducing the cost of durability testing of fuel cell systems and promoting the industrialization of fuel cell electric vehicles.

Simultaneous electrochemical detection of gallic acid and uric acid with p-tert-butylcalix[4]arene-based coordination polymer/mesoporous carbon composite.

Design and synthesis of an efficient electrocatalyst for simultaneous determination of gallic acid (GA) and uric acid (UA) is vital in the biological field. Herein, we synthesized a new p-tert-butylcalix[4]arene-based metal-organic electrocatalyst (Mn-L@MC) by combining Mn-L (H4L = tetrakis[(2-biphenylcarboxyl)oxy]-p-tertbutylcalix[4]arene) and mesoporous carbon (MC) via a simple mechanical grinding method. Synergistic effect between Mn-L and MC made the Mn-L@MC composite behave high-efficiency electrocatalytic performance toward simultaneous detection of GA and UA. Under optimal experimental conditions, the Mn-L@MC-2 electrode material featured relatively wide linear range (0.5-90 µM) for the two analytes, and low determination limits of 0.043 µM for GA and 0.059 µM for UA. The remarkable electrochemical detection behavior of Mn-L@MC-2 electrode material toward GA and UA are comparable to those known sensors containing precious metals. The Mn-L@MC-2 material exhibited high selectivity, superior reproducibility, and acceptable stability during the determination of the two analytes. The sensor was assembled to simultaneously detect GA and UA in healthy human urine with satisfactory recoveries.

Rod-like Co based metal-organic framework embedded into mesoporous carbon composite modified glassy carbon electrode for effective detection of pyrazinamide and isonicotinyl hydrazide in biological samples.

Herein, we report a novel composite fabricated via embedding rod-like Co based metal-organic framework (Co-MOF-74) crystals into MC matrix for the first time. The introduction of MC astricts the size of Co-MOF-74 crystals, enlarges the pore size and improves the electrical conductivity, which lead to the good electrochemical properties of the composite. The fabricated sensor based on Co-MOF-74@MC exhibits superior electrocatalytic activity toward the reduction of pyrazinamide (PZA) and the oxidation of isonicotinyl hydrazide (INZ). Under optimized conditions, the sensor shows two linear ranges from 0.3 to 46.5 µM and 46.5-166.5 µM with a high sensitivity of 7.2 µA µM-1 cm-2 and a detection limit of 0.21 µM for the determination of PZA. The electroanalytical sensing of INZ also gives two linear ranges of 0.15-1.55 µM and 1.55-592.55 µM with a detection limit of 0.094 µM. The mechanism involved was also discussed, briefly. The sensor is assessed toward the detection of PZA and INZ in human serum and urine samples. Recovery values varied from 97.08 to 103.20% for PZA sensing and 96.67-102.90% for INZ sensing, revealing the promising practicality of sensor for PZA and INZ detection.

Highly uniform porous silica layer open-tubular capillary columns produced via in-situ biphasic sol-Gel processing for open-tubular capillary electrochromatography.

We report a highly uniform porous layer open tubular (PLOT) column for capillary electrochromatography (CEC) analysis. The PLOT column is easily fabricated using a single-step in-situ biphasic reaction, producing homogeneous porous-layer modified surface with ∼240 nm thickness in a 50 µm-id capillary. CEC performance of the PLOT column has been investigated and optimized under various experimental parameters. Using a mixture of naphthalene and biphenyl as the test sample, we show that the PLOT column exhibits good separation efficiency with resolution >3.0 and theoretical plate numbers over 6 × 104, as well as good intra-/inter-day repeatability and column-to-column repeatability. The column has been successfully applied for CEC analysis of three different types of samples without any further modification of the columns, including complicated peptide products from tryptic-digestion of proteins (lysozyme and BSA), ß-blockers (basic samples) and polycyclic aromatic hydrocarbons (neutral samples). Efficient separation has been achieved, which could be attributed to the enhanced surface-to-volume ratio of the PLOT column that will increase the interaction between solid phase and mobile phase in CEC. In addition, base-line separation of neutral samples indicates the reversed phase chromatographic property of the PLOT column, which could be induced by the residue of hexadecyltrimethylammonium bromide used in the fabrication process. Our study show that the present PLOT column is a promising approach that can significantly enhance CEC separation efficiency and could be of potential value in analysis of various different samples.

[Change of Plasma Interleukin-17 Level in Patients with Extranodal NK/T-Cell Lymphoma and Its Clinical Significance].

OBJECTIVE: To investigate the clinical significance of interleukin-17 (IL-17) level in patients with extranodal NK/T-cell lymphoma(ENKTL). METHODS: Eighty patients with nasal ENKTL who received radiotherapy, chemotherapy or radiotherapy combined with chemotherapy from January 2011 to January 2012 were enrolled in the study. Eighty healthy volunteers were selected as the controls (control group). About 5 ml of peripheral blood was collected from all patients and controls. IL-17 level was determined by ELISA. The age, sex, ECOG score, B symptoms, LDH level, lymph node involvment, Ann Arbor stage, IPI, KPI, peripheral blood lymphocyte and lymph node metastasis, number of lymphocytes and monocytes in peripheral blood were recorded. All patients were followed up for 3 year progression-free survival (PFS) and overall survival (OS). RESULTS: The average IL-17 level in patients with ENKTL was 6.48 pg/ml and the average concentration of IL-17 in control group was 0.56 pg/ml (P<0.01). The level of IL-17 in patients with B-symptoms and lymph node involvement was significantly higher than that in the control group. The differences in IL-17 level were not statistically significant among patients with different age, sex, ECOG, LDH, Ann Arbor stage, IPI, KPI, lymphocyte count and monocyte cell count. The sensitivity and specificity of IL-17 were 74.5% and 73.7% respectively, and the optimal threshold was 3.49 pg/ml and AUC was 0.799 (95% CI: 0.688-0.909) (P<0.01). The PFS and OS were longer in the patients with IL-17≤3.49 pg/ml and longer in the patients without lymph node involvement and Ann Arbor I. Multivariate analysis showed that independent predictors of PFS and OS in patients with ENKTL were plasma IL-17 levels and age (P<0.05). CONCLUSION: ENKTL patients with different clinical characteristics have different levels of IL-17, the different level of IL-17 has different effects on prognosis of patients with ENKTL.

Inorganic-organic hybrid compounds based on octamolybdates and metal-organic fragments with flexible multidentate ligand: syntheses, structures and characterization.

Six polyoxometalate-based (POM) hybrid materials based on octamolybdate building blocks and metal-organic fragments with flexible multidentate ligand, namely [Cu(II)(2)(ttb)(2)(ß-Mo(8)O(26))(H(2)O)(2)]·2H(2)O (1), Cu(I)(4)(ttb)(2)(ß-Mo(8)O(26))(H(2)O) (2), [Cu(I)(4)(ttb)(3)(ß-Mo(8)O(26))] (3), [Ni(2)(ttb)(2)(ß-Mo(8)O(26))(H(2)O)(6)]·2H(2)O (4), [Zn(2)(ttb)(2)(α-Mo(8)O(26))(H(2)O)(2)] (5), and [Ag(4)(ttb)(2)(ß-Mo(8)O(26))] (6), where ttb = 1,3,5-tris(1,2,4-triazol-1-ylmethyl)-2,4,6-trimethyl benzene, have been synthesized under hydrothermal conditions. Their structures have been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, TGA, IR spectra, and electrochemistry. Compounds 1 and 2 exhibit three-dimensional (3D) 2-fold interpenetrating frameworks with (3,6)-connected (4(1)·6(2))(4(2)·6(10)·10(3)) and (3,4)-connected (6(2)·8(1))(2)(6(2)·8(4)) topologies, respectively. We are not aware of any other examples of interpenetrating (3,6)- and (3,4)-connected frameworks which involves the octamolybdates. Compound 3 shows a rare two-dimensional (2D) 2-fold interpenetrating network structure. In compound 4, a 3D supramolecular framework with the channels is constructed by the hydrogen-bonding interactions between (ß-Mo(8)O(26))(4-) polyanions and the Ni-ttb double layers, in which the guest (ß-Mo(8)O(26))(4-) anions are included. If ZnO interactions are considered, the structure of 5 is a 3D (3,4)-connected framework with (4·8(2))(4·8(2)·10(3)) topology. In 6, the ttb ligand as a tetradentate ligand links the Ag atoms to yield a 2D POM-based network. By careful inspection of the structures of 1-6, it can be seen that the ttb ligand, the metal ion and the coordination mode of the octamolybdate anion play important roles in the formation of the POM-based MOFs.

Series of 2D and 3D coordination polymers based on 1,2,3,4-benzenetetracarboxylate and N-donor ligands: synthesis, topological structures, and photoluminescent properties.

Nine new coordination polymers, namely, [Mn(2)(L)(H(2)O)(4)].H(2)O (1), [Cd(L)(0.5)(H(2)O)] (2), [Zn(5)(L)(2)(mu(3)-O)(2)(H(2)O)(4)].2H(2)O (3), [Zn(4)(L)(2)(mu(3)-O)(2)][Zn(H(2)O)(5)].2H(2)O (4), [Zn(2)(L)(biim-4)(0.5)(H(2)O)(3)].H(2)O (5), [Cd(2)(L)(bpy)(H(2)O)].2H(2)O.0.5(CH(3)CH(2)OH) (6), [Cu(2)(H(2)L)(2)(bpy)(2)] (7), [Cu(2)(L)(bpy)(H(2)O)] (8), and [Cu(2)(L)(bpy)(1.5)(H(2)O)(2.5)] (9), where H(4)L = 1,2,3,4-benzenetetracarboxylic acid, biim-4 = 1,1'-(1,4-butanediyl)bis(imidazole), and bpy = 4,4'-bipyridine, have been synthesized under hydrothermal conditions. Compound 1 displays a rare trinodal (3,4,7)-connected (4(2).6)(4(5).6)(4(7).6(8).8(6)) topology. 2 possesses an alpha-Po net. 3 is a novel 3D framework based on pentanuclear Zn(II) clusters. By adjustment of the pH values of the reaction mixture of 3 with a Na(2)CO(3) solution, a structurally different compound, 4, was obtained, which exhibits a 3D porous framework with the [Zn(H(2)O)(6)](2+) cations located in the channels. 5 is an unusual example of a trinodal (3,5)-connected network with a Schlafli symbol of (4(2).6)(6(2).8)(4(2).6(2).8(5).10), whereas 6, containing tetranuclear Cd(II) clusters, shows a rare (4,6)-connected (4(4).6(2))(2)(4(4).6(10).8) topology. 7 exhibits a unique polythreading network, while 8 displays a scarce trinodal (3,4,5)-connected self-penetrating network. In comparison with 8, the chiral compound 9 possesses an unprecedented tetranodal (2,4)-connected (7)(7(5).11)(6(2).7(3).8)(2)(6.7(4).10)(2) topology. The effects of the carboxylate ligands, the pH values, the reaction temperatures, the central metals, and the neutral ligands were elucidated. The IR spectra, thermogravimetric analysis, and luminescent properties for the compounds were also investigated.

Poly[bis(mu3-benzene-1,3,5-tricarboxylato-kappa(3)O(1):O(3):O(5))tris[mu2-1,3-bis(imidazol-1-ylmethyl)benzene-kappa(2)N:N']tricobalt(II)] and poly[[diaquabis(mu3-benzene-1,3,5-tricarboxylato-kappa(3)O(1):O(3):O(5))tris[mu2-1,4-bis(imidazol-1-ylmethyl)benzene-kappa(2)N:N']tricobalt(II)] monohydrate].

The title cobalt(II) coordination polymers, [Co3(C9H3O6)2(C14H14N4)3]n, (I), and {[Co3(C9H3O6)2(C14H14N4)3(H2O)2] x H2O}n, (II), present very different coordination and packing properties in spite of the ligand similarity. In (I), three crystallographically distinct Co(II) cations are all four-coordinated by O2N2 donor sets in distorted tetrahedral geometries. The Co(II) centres are connected by benzene-1,3,5-tricarboxylate (BTC) anions and 1,3-bis(imidazol-1-ylmethyl)benzene (L(1)) ligands into a (6(4).8(2))2(8(6))(6.8(2))2 topology framework. The structure of (II) contains two kinds of crystallographically unique Co(II) cations. One Co atom lies on a symmetry centre and is six-coordinated by an O4N2 donor set, and the other Co atom is four-coordinated by an O2N2 donor set. The Co(II) centres are connected by BTC anions and 1,4-bis(imidazol-1-ylmethyl)benzene (L(2)) ligands into a (6(2).8(4))2(6(4).8(2))(6(3))2 framework.

Poly[[(µ(3)-5,6-dicarboxy-bicyclo-[2.2.2]oct-7-ene-2,3-dicarboxyl-ato)(1,10-phenanthroline)copper(II)] monohydrate].

In the title compound, {[Cu(C(12)H(10)O(8))(C(12)H(8)N(2))]·H(2)O}(n), the Cu(II) ion is five-coordinated by two N atoms from one phenanthroline ligand and three O atoms from three different H(2)L(2-) anions (H(4)L is bicyclo-[2.2.2]oct-7-ene-2,3,5,6-tetra-carboxylic acid) in a distorted square-pyramidal geometry. Each H(2)L(2-) ion bridges three Cu(II) atoms to form a zigzag sheet parallel to the ab plane. The crystal structure is consolidated by O-H⋯O hydrogen bonds.

Organic-acid effect on the structures of a series of lead(II) complexes.

An investigation into the dependence of coordination polymer architectures on organic-acid ligands is reported on the basis of the reaction of Pb(NO3)2 and eight structurally related organic-acid ligands in the presence or absence of N-donor chelating ligands. Eight novel lead(II)-organic architectures, [Pb(adip)(dpdp)]2 1, [Pb(glu)(dpdp)] 2, [Pb(suc)(dpdp)] 3, [Pb(fum)(dpdp)] . H2O 4, [Pb2(oba)(dpdp)2] . 2(dpdp).2(NO3).2H2O 5, [Pb2(1,4-bdc)2(dpdp)2] . H2O 6, [Pb(dpdc)(dpdp)] 7, and [Pb(1,3-bdc)(dpdp)] . H2O 8, where dpdp = dipyrido[3,2-a:2',3'-c]-phenazine, H2adip = adipic acid, H2glu = glutaric acid, H2suc = succinic acid, H2fum = fumaric acid, H2oba = 4,4'-oxybis(benzoic acid), 1,4-H2bdc = benzene-1,4-dicarboxylic acid, H2dpdc = 2,2'-diphenyldicarboxylic acid, and 1,3-H2bdc = benzene-1,3-dicarboxylic acid, were successfully synthesized under hydrothermal conditions through varying the organic-acid linkers and structurally characterized by X-ray crystallography. Compounds 1-8 crystallize in the presence of organic-acid linkers as well as secondary N-donor chelating ligands. Diverse structures were observed for these complexes. 1 and 5 have dinuclear structures, which are further stacked via strong pi-pi interactions to form 2D layers. 2-3 and 6-8 feature chain structures, which are connected by strong pi-pi interactions to result in 2D and 3D supramolecular architectures. Compound 4 contains 2D layers, which are further extended to a 3D structure by pi-pi interactions. A systematic structural comparison of these 8 complexes indicates that the organic-acid structures have essential roles in the framework formation of the Pb(II) complexes.