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Modification and degradation of habitats outside the boundaries of a national park may result in the park's integrity being compromised. Thus, the present study aims to document variation in freshwater fish and water quality of tropical forest streams ad-jacent to the western boundary of Kinabalu Park, Sabah. Concurrently, fish samples and environmental parameters were collected at six stations covering a total stream-line length of 10 km. The three most abundant species were Tor tambra(34.4%), Bar-bodes sealei(19.5%), and Lobocheilos ovalis(12.4%). Tor tambraexhibited a nega-tive allometric growth pattern (coefficient < 3) and was in poor to fair condition (0.8 < Fulton’s condition factor < 1.2). The highest fish abundance was found in down-stream stations with species addition. Metrics of diversity, such as Shannon's diversity index and the Margalef index of species richness, decreased as elevation increased from 100 to 600 metres above sea level. The water quality of the forest streams is good, classified as Class I and/or Class II by Malaysia's National Water Quality Stand-ards, except for ammoniacalnitrogen at station 6, which was classified as Class III. Higher turbidity, orthophosphate, and ammoniacal-nitrogen values were found near the Podos village. Inconclusion, the altitudinal gradient of fish biodiversity was ob-served in the forest streams near Kinabalu Park.Regular water quality monitoring of the downstream river is necessary, as indicated by the potential domestic impacts on the river.

Treatment of [Co(N2)(tBuPNP)] (tBuPNP = anion of 2,5-bis(di-tert-butylphosphinomethyl)pyrrole) with one equivalent of an aryl azide generates the four-coordinate imido complexes [Co(NAr)(tBuPNP)] (Ar = mesityl, phenyl, or 4-tBu-phenyl). X-ray crystallographic analysis of the compounds shows an unusual square-planar geometry about cobalt with nearly linear imido units. In the presence of the hydrogen atom donor, TEMPOH, [Co(NPh)(tBuPNP)] undergoes addition of the H atom to the imido nitrogen to generate the corresponding amido complex, [Co(NHPh)(tBuPNP)], whose structure and composition were verified by independent synthesis. Despite the observation of H atom transfer reactivity with TEMPOH, the imido complexes do not show catalytic activity for C–H amination or aziridination for several substrates examined. In the case of [Co(NPh)(tBuPNP)], addition of excess azide produced the tetrazido complex, [Co(N4Ph2)(tBuPNP)], whose bond metrics were most consistent with an anionic Ph2N4 ligand. Density Functional Theory (DFT) investigations of the imido and tetrazido species suggest that they adopt a ground state best described as possessing a low-spin cobalt(II) ion ferromagnetically coupled to an iminyl radical. [ABSTRACT FROM AUTHOR]

The 4‐carboxylates of 1,2,3‐triazine 1‐oxides undergo [3+2] cycloaddition with in situ generated benzynes and naphthyne and also with cyclooctyne that, following extrusion of dinitrogen, form isoxazole‐3‐propenoate derivatives in high yields and diastereocontrol. This practical method occurs at room temperature and provides a wide range of isoxazole‐based heterocycles with diverse functionality. 1,2‐Naphthyne, an unsymmetrical alkyne, forms only one regioisomeric product, exemplifying inherent regioselectivity. Although high, stereoselectivity is not 100 % in most cases, indicating that the loss of dinitrogen is stepwise. Derivative reactions of benzisoxazoles suggest their versatility. [ABSTRACT FROM AUTHOR]

A novel fluorescent hydrogen-bonded organic framework with a double fold interpenetrated structure, HOF-22, has been successfully constructed and structurally characterized. HOF-22 is capable of sensitive detection of two representative organic arsenics from aqueous solution. Key words: hydrogen-bonded organic frameworks (HOFs), sensing, fluorescence quenching, organic arsenics. Nous avons construit un nouveau reseau organique a liaisons hydrogene fluorescent comportant une structure a deux motifs interpenetres, le reseau HOF-22, et avons caracterise sa structure. Nous avons ensuite demontre que HOF-22 peut etre utilise pour effectuer la detection sensible en solution aqueuse de deux composes organiques d'arsenic representatifs. [Traduit par la Redaction] Mots-cles: reseaux organiques a liaisons hydrogene (HOF), detection, extinction de fluorescence, composes organiques d'arsenic., Introduction Hydrogen-bonded organic frameworks (HOFs) are a kind of crystalline porous solid constructed by organic building units (OBUs) through hydrogen bonding interactions. (1,2) Similar with other famous porous materials like [...]

A new cobalt(II) coordination polymer 'Cp-Co' has been designed and synthesized. The construction includes cobalt(II) as the central metal core along with 1,4-benzenedicarboxylic acid and the spacer 3,5-diamino-1,2,4-triazole obtained by a solvothermal method. The architecture of 'Cp-Co' was established using single X-ray crystallography and the topology of the coordination polymer. The 'Cp-Co' exhibited a periodic 3D framework. Furthermore, infrared spectroscopy (FT-IR), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM) and Brunauer–Emmett–Teller (BET) analysis further supported the structure of 'Cp-Co'. The prepared material was explored as a catalyst for the photocatalytic degradation of methyl green (MG) dye and displayed outstanding degradation efficiency under visible light radiation. The experimental design was explored towards optimization of the reaction variables, such as catalyst dose, MG dye concentration, etc. It was found that 10 mg of Cp-Co with 150 mg L−1 MG resulted in 99.77% photocatalytic efficiency within 60 min of visible light irradiation. The kinetic data was simulated using the Langmuir–Hinshelwood kinetic model and the value of the apparent rate constant (Kapp) was found to be 0.020 min−1, 0.024 min−1 and 0.029 min−1 for 50, 100 and 150 mg L−1 MG concentrations. The trapping experiments suggested the involvement of a superoxide anion radical (O2−˙) in the degradation of MG. [ABSTRACT FROM AUTHOR]

C34H54N8O2S8Zn2, monoclinic, C2/c (no. 15), a = 20.192(7) Å, b = 16.448(5) Å, c = 14.150(5) Å, β = 102.368(8)°, V = 4590(3) Å3, Z = 4, Rgt(F) = 0.052, wRref(F2) = 0.123, T = 98 K.