Boronyl as a terminal ligand in boron oxide clusters: hexagonal ring C(2v) B6O4 and ethylene-like D(2h) B6O4(-/2-).

Considerable recent research effort has been devoted to the development of boronyl (BO) chemistry. Here we predict three perfectly planar boron boronyl clusters: C2v B6O4 (1, (1)A1), D2h B6O4(−) (2, (2)B3u), and D2h B6O4(2−) (3, (1)Ag). These are established as the global-minimum structures on the basis of the coalescence kick and basin hopping structural searches and electronic structure calculations at the B3LYP/aug-cc-pVTZ level, with complementary CCSD/6-311+G* and single-point CCSD(T)/6-311+G*//B3LYP/aug-cc-pVTZ calculations for 2. The C2v B6O4 neutral cluster features a hexagonal B4O2 ring with two terminal BO groups. The D2h B6O4(−/2−) clusters have ethylene-like structures and are readily formulated as B2(BO)4(−/2−), in which a B2 core with double bond character is bonded to four terminal BO groups. Chemical bonding analyses show that B6O4 (1) possesses an aromatic π bonding system with three delocalized, six-centered π bonds over the hexagonal ring, rendering it an inorganic analogue of benzene, whereas the B6O4(−/2−) (2 and 3) species closely resemble ethylene in terms of structures and bonding. This work provides new examples for the analogy between boron oxides and hydrocarbons.

Subchronic safety evaluation of CMS-1 (a botanical antihypertensive product derived from Semen Cnidium monnieri) in Sprague-Dawley rats and beagle dogs.

CMS-1, mainly composed of imperatorin as its active compound, is a partially purified fraction of a Chinese herbal medicine, Semen Cnidium monnieri. CMS-1 has the potential to be further developed as a new treatment for hypertension. Thus, we studied its toxicity in both Sprague-Dawley rats and beagle dogs. Rats (0-900mg/kg/day) and dogs (0-450mg/kg/day) received CMS-1 orally for 30 consecutive days, followed by a 15-day recovery period. The major target organs of CMS-1 toxicity are the GI (inappetence), liver (hepatocellular necrosis, enzyme elevation), thymus (atrophy), cardiovascular (hypotension), changes in ECG T and P waveforms, elevation of nitrous oxide levels and hematological (RBC parameters disturbances) systems. Most treatment-induced adverse effects were reversible or showed a progressive recovery upon discontinuation of the treatment. The No Observed Adverse Effect Level (NOAEL) was 100mg/kg/day for rats and 50mg/kg/day for dogs. This non-clinical study suggests that clinical monitoring of CMS-1 in patients should focus on the gastrointestinal system, blood tests for liver functions, electrolytes, and blood homeostasis, cardiovascular functions, and immune functions.

[Effect of phosphate and organic acid addition on passivation of simulated Pb contaminated soil and the stability of the product].

Organic acids can improve the phosphorus availability, influence the immobilization of heavy metals in soil, and has very complicated function in phosphorus activation and heavy metal passivation. This research took simulated Pb contaminated soil as material, phosphate and citric acid as remediation matter, adopted BCR continuous extraction, 0.01 mol · L(-1) CaCl2 and toxicity characteristic leaching procedure (TCLP) to evaluate the remediation effect. Besides, malic acid and NaNO3 were taken as desorption reagents to discuss the stability of the phosphorus-citric acid-Pb system. The results showed that: in the absence of citric acid, the amount of acid extracted Pb decreased along with the increase of P concentration; when the P concentration was 100 and 400 mg · kg(-1), acid extractable Pb increased with the increasing of citric acid concentration. However, residual Pb changed in the opposite direction from acid extractable Pb. The phenomenon showed that P improved the bioavailability of Pb, while citric acid had the opposite effect. With a certain organic acid concentration, extractable Pb contents extracted by 0.01 mol · L(-1) CaCl2 and TCLP both decreased with the increasing P concentration, therefore, P had immobilization effect on Pb in contaminated soil. But at a fixed P concentration, extractable Pb contents by 0.01 mol · L(-1) CaCl2 and TCLP changed in the opposite trend with the increasing citric acid concentration. The desorption rate of Pb in soil increased with the increasing malic acid concentration, the decreasing pH and the increasing ionic strength. The desorption extent of Pb in soil with P only was lower than that with both P and citric acid. But the stability of Pb passivated by the former was higher.

[Studies on agronomic traits of seedlings from different F1 generations of Dendrobium officinale].

OBJECTIVE: To select superior mating combinations from different F1 generations of Dendrobium officinale. METHOD: Twenty-six superior parents from four provenances were selected to make up 26 mating combinations. The agronomic traits of different F1 generation were measured, counted, and analyzed by DPS software. RESULT: There were significant differences between different mating combinations among F1 generations. The variation among full-sib families was significantly higher than that among half-sib families, while the variation inside full-sib families was significantly lower than that inside half-sib families. Twelve agronomic traits were simplified into four principal components, of which the accumulative contribution rate was 84.127 3%. Twenty-six mating combinations have been divided into six groups, plants from the fifth and sixth group grew much better than the others. CONCLUSION: The selection of parents should be emphasized by using hybrid vigor. There were higher genetic gains and superior uniformity inside families when selection and breeding occurs in full-sib families than in half-sib families. Eight superior full-sib families (83 x 34, 66 x 9, 68 x 2, 91 x 69, 66 x 65, 69 x 91, 17 x 66, 66 x 17) have been selected which showed a good agronomic traits of seedlings.

[Pharmacognostic identification of Ferula syreitschikowii].

OBJECTIVE: To identify Ferula syreitschikowii by identification of pharmacognosy and provide the scientific evidence for its identification and application. METHODS: The crude drug identification, morphological, UV spectrum identifications, microscopic identification and thin layer chromatography (TLC) were adopted. RESULTS: There were specialization in morphology, microscopic characteristic, UV spectrum identifications and thin layer chromatography (TLC). CONCLUSION: These characteristics can be used for scientific basis for gruffs identification of crude drug and providing reference information for further development.