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1.
中国隐姬蜂属(膜翅目,姬蜂科)研究   总被引:4,自引:4,他引:0  
报道采自我国的隐姬蜂属Cryptopimpla Taschenberg2新种:短尾隐姬蜂Cryptopimpla brevis Sheng,sp.nov.和河南隐姬蜂Cryptopimpla henanensis Sheng,sp.nov.,中国1新纪录种:古北隐姬蜂Cryptopimpla helvetica Brauns,1901.编制了中国已知种检索表.模式标本保存在国家林业局森林病虫害防治总站.  相似文献   

2.
报道在江西发现的差齿姬蜂属Thymaris Frster,1869的种类,其中有3新种:黄足差齿姬蜂Th. flavipedalis sp.nov.,红颈差齿姬蜂Th. ruficollaris sp.nov.,沟差齿姬蜂Th. sulcatus sp. nov.和中国1新纪录种纺差齿姬蜂Th. clotho Morley,1913。指出了新种与近似种的鉴别特征,并附彩色特征图。编制了该属中国已知种的检索表。  相似文献   

3.
中国兜姬蜂属分类研究(膜翅目,姬蜂科)   总被引:5,自引:4,他引:1  
报道兜姬蜂属Dolichomitus Smith 1新种:嵩兜姬蜂Dolichomitus songxianicus Sheng,sp.nov.及中国2新纪录种:头兜姬蜂D.cephalotes(Holmgren)、卡西兜姬蜂D.khasianus Gupta et Tikar.编制了中国已知的14种2亚种检索表.  相似文献   

4.
报道在江西省发现的我国姬蜂科1新纪录属:全沟姬蜂属 Amrapalia Gupta et Jonathan,1970,并记述2新种:黄面全沟姬蜂 A.flavifacialis sp.nov.、黑面全沟姬蜂 A.nigrifacialis sp.nov..指出了与近似种的鉴别特征.编制了我国已知种检索表.  相似文献   

5.
中国的耕姬蜂属(膜翅目,姬蜂科)及一新种   总被引:2,自引:2,他引:0  
记述采自河南省宝天曼自然保护区的耕姬蜂属Arotes Gravenhorst,1829的新种,斑耕姬蜂Arotes moculatus sp.nov.和采自辽宁及吉林的1已知种:白带耕姬蜂A.albicinctus albicinctus Gravenhorst,1829.编制了耕姬蜂属中国已知种检索表.  相似文献   

6.
中国蛀姬蜂属(膜翅目,姬蜂科)种类及一新种   总被引:1,自引:1,他引:0  
报道蛀姬蜂属Schreineria Schreiner,1905中国已知种类及在江西省发现的该属l新种:凹蛀姬蜂Schreineria recava sp.nov..编制了中国已知种检索表.  相似文献   

7.
盛茂领  裴海潮 《昆虫学报》2002,45(Z1):96-98
 报道了采自河南的角姬蜂属Cosmoconus Foerster 二新种:西峡角姬蜂 C. xixiaens is Sheng, sp.nov. 和斑角姬蜂C. maculiventris Sheng, sp.nov.,并指出了与近 似种的主要区别特征。  相似文献   

8.
报道在江西和河南发现的浮姬蜂属Phobetes Frster,1869的种类,其中有2新种:白环浮姬蜂Ph.albiannularissp.nov.和河南浮姬蜂Ph.henanensis sp.nov.;中国1新纪录种:北海道浮姬蜂Ph.sapporensis(Uchida,1930)。指出了新种与近似种的鉴别特征,并附彩色特征图。编制了该属中国已知种的检索表。  相似文献   

9.
报道在北京发现的凿姬蜂属Xorides Latreille,1809 1新种:黑斑凿姬蜂,新种Xoride(Xoride)nigrimaculatus sp.nov.,指出了与近似种的鉴别特征.  相似文献   

10.
中国姬蜂科(膜翅目)二新种(英文)   总被引:1,自引:0,他引:1  
本文报道采自河南省伏牛山区的姬蜂科Ichneumonidae二新种 :暗足大食姬蜂ZabrachypusatripedalisSheng ,sp .nov .和斑三钩姬蜂TriancyramaculataSheng ,sp .nov .各新种分别与其近似种作了比较。标本保存在国家林业局森林病虫害防治总站  相似文献   

11.
For the rational design of a stable collagen triple helix according to the conventional rule that the pyrrolidine puckerings of Pro, 4-hydroxyproline (Hyp) and 4-fluoroproline (fPro) should be down at the X-position and up at the Y-position in the X-Y-Gly repeated sequence for enhancing the triple helix propensities of collagen model peptides, a series of peptides were prepared in which X- and Y-positions were altogether occupied by Hyp(R), Hyp(S), fPro(R) or fPro(S). Contrary to our presumption that inducing the X-Y residues to adopt a down-up conformation would result in an increase in the thermal stability of peptides, the triple helices of (Hyp(S)-Hyp(R)-Gly)(10) and (fPro(S)-fPro(R)-Gly)(10) were less stable than those of (Pro-Hyp(R)-Gly)(10) and (Pro-fPro(R)-Gly)(10), respectively. As reported by B?chinger's and Zagari's groups, (Hyp(R)-Hyp(R)-Gly)(10) which could have an up-up conformation unfavorable for the triple helix, formed a triple helix that has a high thermal stability close to that of (Pro-Hyp(R)-Gly)(10). These results clearly show that the empirical rule based on the conformational preference of pyrrolidine ring at each of X and Y residues should not be regarded as still valid, at least for predicting the stability of collagen models in which both X and Y residues have electronegative groups at the 4-position.  相似文献   

12.
Xia Z  Zhuang J 《Luminescence》2012,27(5):379-381
A novel blue‐emitting Sr3.5Y6.5O2(PO4)1.5(SiO4)4.5:Eu2+ phosphor was synthesized via a solid‐state reaction. Powder X‐ray diffraction (XRD) analysis demonstrated that the Sr3.5Y6.5O2(PO4)1.5(SiO4)4.5 host had a hexagonal crystal structure in the space group P63/m and unit cell parameters a = 9.418 Å, c = 6.900 Å. The as‐prepared phosphor showed a blue emission and all the main emission peaks were located at around 466 nm for different excitation wavelengths of 297, 333 and 391 nm. The temperature dependence of the photoluminescence property was investigated in the range 20–250 °C, and the emission intensity decreased to 71% of the initial value at room temperature on increasing the temperature to 150 °C. According to the classical theory of fluorescent thermal quenching, the activation energy (ΔE) for the thermal quenching luminescence of the as‐prepared Sr3.45Y6.5O2(PO4)1.5(SiO4)4.5:0.05Eu2+ phosphor was determined to be 0.20 eV. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

13.
The enzymes chlorocatechol-1,2-dioxygenase, chloromuconate cycloisomerase, dienelactone hydrolase, and maleylacetate reductase allow Ralstonia eutropha JMP134(pJP4) to degrade chlorocatechols formed during growth in 2,4-dichlorophenoxyacetate or 3-chlorobenzoate (3-CB). There are two gene modules located in plasmid pJP4, tfdC(I)D(I)E(I)F(I) (module I) and tfdD(II)C(II)E(II)F(II) (module II), putatively encoding these enzymes. To assess the role of both tfd modules in the degradation of chloroaromatics, each module was cloned into the medium-copy-number plasmid vector pBBR1MCS-2 under the control of the tfdR regulatory gene. These constructs were introduced into R. eutropha JMP222 (a JMP134 derivative lacking pJP4) and Pseudomonas putida KT2442, two strains able to transform 3-CB into chlorocatechols. Specific activities in cell extracts of chlorocatechol-1,2-dioxygenase (tfdC), chloromuconate cycloisomerase (tfdD), and dienelactone hydrolase (tfdE) were 2 to 50 times higher for microorganisms containing module I compared to those containing module II. In contrast, a significantly (50-fold) higher activity of maleylacetate reductase (tfdF) was observed in cell extracts of microorganisms containing module II compared to module I. The R. eutropha JMP222 derivative containing tfdR-tfdC(I)D(I)E(I)F(I) grew four times faster in liquid cultures with 3-CB as a sole carbon and energy source than in cultures containing tfdR-tfdD(II)C(II)E(II)F(II). In the case of P. putida KT2442, only the derivative containing module I was able to grow in liquid cultures of 3-CB. These results indicate that efficient degradation of 3-CB by R. eutropha JMP134(pJP4) requires the two tfd modules such that TfdCDE is likely supplied primarily by module I, while TfdF is likely supplied by module II.  相似文献   

14.
Sim GE  Goh CJ  Loh CS 《Plant cell reports》2008,27(8):1281-1289
We analysed the endogenous cytokinin levels of Dendrobium Madame Thong-In seedlings grown in vitro during vegetative and flowering-inductive periods. HPLC was used to fractionate the extracts and radioimmunoassay (RIA) was used for assay of zeatin (Z), dihydrozeatin (DZ), N(6)-(Delta(2)-isopentenyl)-adenine (iP) and their derivatives. Coconut water used in experiments was found to contain high level (>136 pmol ml(-1)) of zeatin riboside (ZR). Protocorms and seedlings cultured in medium with coconut water were found to contain 0.5-3.9 pmol g(-1) FW of the cytokinins analysed. Seedlings (1.0-1.5 cm) cultured in flowering-inductive liquid medium containing 6-benzyladenine (BA, 4.4 muM) and coconut water (CW, 15%) contained up to 200 and 133 pmol g(-1) FW of iP and iPA, respectively. These levels were significantly higher than all other cytokinins analysed in seedlings of the same stage and were about 80- to 150-folds higher than seedlings cultured in non-inductive medium. During the transitional (vegetative to reproductive) stage, the endogenous levels of iP (178 pmol g(-1) FW) and iPA (63 pmol g(-1) FW) were also significantly higher than cytokinins in the zeatine (Z) and dihydrozeatin (DZ) families in the same seedlings. Seedlings that grew on inductive medium but remained vegetative contained lower levels of iPA. The importance of the profiles of iP and its derivatives in induction of in vitro flowering of D. Madame Thong-In is discussed.  相似文献   

15.
The biology of the fruit fly Bactrocera tau, an important horticultural pest, was studied under laboratory conditions at 25°C and 60–70% relative humidity on Cucurbita maxima. The duration of mating averaged 408.03 ± 235.93 min. After mating, the female fly had a preoviposition period of 11.7 ± 4.49 days. The oviposition rate was 9.9 ± 8.50 eggs and fecundity was 464.6 ± 67.98 eggs/female. Eggs were elliptical, smooth and shiny white, turning darker as hatching approached, and measured 1.30 ± 0.07 mm × 0.24 ± 0.04 mm. The chorion has polygonal microsculpturing and is species-specific with polygonal walls. The egg period lasts for 1.3 ± 0.41 days. The duration of the larval period is 1.2 ± 0.42, 1.7 ± 0.48 and 4.0 ± 0.94 days for first, second and third instars, respectively. Pupation occurs in the sand or soil and pupal periods are 7.0 ± 0.47 days. The life cycle from egg to adult was completed in 14.2 ± 1.69 days; the longevity of mated females and males was 130.33 ± 14.18 and 104.66 ± 31.21 days, respectively. At least two to three generations were observed from June 2008 to June 2009.  相似文献   

16.
This article reports on the optical properties of Er3+ ions doped CdO–Bi2O3–B2O3 (CdBiB) glasses. The materials were characterized by optical absorption and emission spectra. By using Judd–Ofelt theory, the intensity parameters Ωλ (λ = 2, 4, 6) and also oscillatory strengths were calculated from the absorption spectra. The results were used to compute the radiative properties of Er3+:CdBiB glasses. The concentration quenching and energy transfer from Yb3+–Er3+ were explained. The stimulated emission cross‐section, full width at half maximum (FWHM) and FWHM × values are also calculated for all the Er3+:CdBiB glasses. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

17.
R M Wartell 《Biopolymers》1972,11(4):745-759
Helix–coil transition curves are calculated for poly (dA) poly(dT) and poly (dA-dT) poly (dA-dT) using the integral equation approach of Goel and Montroll.5 The transitions are described by the loop entropy model with the exponent of the loop entropy factor, k, remaining an arbitrary constant. The theoretical calculations are compared with experimental transition curves of the two polymers. Results indicate that the stacking energies for these two polymers differ by about 1 kcal/mole of base pairs. Also, a fit between theory and experiment was not possible for k > 1.70.  相似文献   

18.
The formation of cationic palladium(II)complexes [TrpyPdII]+X by salt metathesis of the respective trifluoroacetates with different salts of weakly coordinating anions X was investigated. With non-hydrolizable counterions, cationic mono- and dinuclear complexes are observed depending on the nature of the anion X and the solvent. The mononuclear cations, which are only formed with X = BArF, most probably carry a weakly bound molecule of dichloromethane at the fourth coordination site of PdII. When treated with diazoalkanes, only these are sufficiently reactive to form carbene complexes. Four- and five coordinate Lewis base adducts [TrpyPdIIL]+ with L = CH3NC, tBuNH2, PMe3, PEt3 and PiPr3 and [TrpyPdIIL2]+ with L = PMe3 were prepared from the mononuclear cations [TrpyPdII]+BArF−. From structural studies it becomes apparent, that the formation of stable five coordinate PdII species is restricted to medium size ligands and depends on the delicate balance between the steric influence of L and the strain, which is induced on the TrpyPdII unit.  相似文献   

19.
20.
Synthesis and single crystal X-ray structures of the first paramagnetic transition metal complexes containing chiral ethylenedithio-tetrathiafulvalene-oxazoline (EDT-TTF-OX) 1a-c and ethylenedithio-tetrathiafulvalene-thiomethyloxazoline 2 (EDT-TTF-(SMe)OX) ligands based on copper (II) and cobalt (II) are described. The racemic [EDT-TTF-OX][Cu(hfac)2] complex 3a crystallizes in the triclinic centrosymmetric space group , whereas the enantiopure counterparts 3b-c crystallize in the triclinic non-centrosymmetric space group P1. Cu(II) adopts a distorted square pyramidal coordination geometry, a much weaker Cu?STTF interaction also being identified. The same coordination pattern around Cu(II) is observed in the complex [(rac)-EDT-TTF-(SMe)OX][Cu(hfac)2] (4) in spite of the bidentate nature of the redox active ligand. DFT theoretical calculations afforded two equilibrium configurations for a corresponding model complex, in which the metal centre establishes secondary coordination either with one STTF or with the SMe group. The same ligand coordinates the cobalt (II) to afford the octahedral complex [(rac)-EDT-TTF-(SMe)OX][Co(hfac)2] (5). In all these novel complexes, the paramagnetic centres are structurally and magnetically isolated. Cyclic voltammetry measurements show the stability of the radical cation species.  相似文献   

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