The Diazosafranin Method; Control of Nitrite Concentration and Refinements in Specificity

Safranin is diazotized by using the customary molar ratio—dye, 1:HCl, 3:NaNO₂l. Partly oxidized NaNO₂ can be used, if necessary, by increasing the concentration of its solution enough to cause the normal color change from red to deep blue to occur within 2 min after adding the NaNO₂. To avoid carrying over excess HNO₂ into the alkaline coupling solution, 1 ml of 3% alcoholic urea solution (30 mg) is added for each milliliter excess of 1 N NaNO₂ used. Any free HNO₂ remaining at the end of the diazotization period produces a deep blue violet on starch-KI paper. Prolonged acid washing may be applied after coupling to decolorize cationic dye staining or triazenes. Na₂S₂O₄, TiCl₃ or SnCl₂ may be used to bleach true azo colorations. This decolorization is not limited to newly formed azo compounds with tissue.     

A Silver Impregnation Method for Nervous Tissue Suitable for Routine use with Mounted Sections

A simple, reliable silver impregnation method for nervous tissue is described for tissues fixed in various fixatives including formalin, Bouin, and Sum. Sections are impregnated in a solution containing 1 g Protargol, 2 ml of a 1% Cu(NO₃)₂ solution, 2 ml of a 1% AgNO₃ solution, and 2-4 drops 30% H₂O₂ in 100 ml distilled water. Sections are impregnated 4-5 days at 37 C and thereafter reduced in a hydroquinone-formalin solution. This is followed by gold toning and subsequent reduction, dehydration and mounting. This method has been found to be very reliable and selective.     

营养液照光引起的化学变化及其对植物生长的影响

水稻(Oryza sativa)根系照光实验表明, 光的效应随循环水影响到不照光的植株, 暗示营养液中发生了化学变化。在Si (K₂SiO₃)和Fe (FeEDTA)组成的溶液模拟系统中, 分别照射LED-紫光或阳光, 观察到反应液的OD₄₀₀值随光照时间的延长而增加。光照引起的化学变化发生在FeEDTA和K₂SiO₃之间。化学变化只与光能量有关, 与溶液温度无关, 这是一种光化学反应。光化反应溶液的光吸收从OD₃₆₀到OD₅₆₀都有明显增高。LED-蓝光和阳光诱导产生的并含FeEDTA-SiO₃成分并能吸收光的二元螯合铁硅酸盐复合物附着在衬底膜上, 形成三元复合物。衬底膜上可见大量的颗粒, 其中有些是反光的微晶颗粒。除LED-蓝光和阳光外, LED-紫光、LED-红光和LED-红外光也能诱导产生光谱性质相同的螯合铁硅酸盐复合物。制备含螯合铁硅酸盐复合分子的溶液并进行植物生长实验, 结果显示小球藻生长好, 死亡的藻体分解褪色后留下的是褐色的蓬松团状铁-硅化物。经螯合铁硅酸盐复合物处理的水稻干重增加明显。     

A Simplified Nissl Stain with Thionin

Recently two articles on the use of thionin as a cell stain for neurological materials have appeared. One utilizes a solution buffered in the acid range³; the other uses a “steaming” staining solution⁴. For some time we have been using thionin as a routine stain after either formalin or alcohol fixation and our method is so simple and has given such satisfactory results with a variety of brands of thionin that it seemed to be worthy of more general use. Briefly the method consists of placing the celloidin sections in a 0.05% solution of Li₂CO₃ (the percentage of Li₂CO₃ is non-critical) for about 5 minutes and then grossly overstaining in a 0.25% solution of thionin in a 0.05% solution of Li₂CO₃ in distilled water. The overstaining is necessary if all the stain is to be removed from the background. The sections are then passed through distilled water, 70 or 80% alcohol, two changes of butyl alcohol, two changes of xylene and mounted with Clarite. For most material, split mica cover-slips are quite satisfactory. The time of differentiation may be considerably lessened by the use of the differentiator recommended by Neumann (1942) except that we find the chloroform superfluous and transfer the sections to the aniline solution from 95% alcohol. Less fading seems to occur if the aniline differentiator is followed by a saturated solution of Li₂CO₃ in 95% alcohol.     

Assaying Actual Hematein Content of Commercial Hematoxylins and Hemateins

Hematein-free hematoxylin (HFH) was prepared by a modification of the procedure of Palmer and Lillie (Histochemie, 5: 44-54, 1965). Fifty mg of HFH were dissolved in 5 mg of ethylene glycol and then 45 nil of an aqueous solution of 2.25 gm KAl(SO₄)₂. 12H₂O and 5.445 mg KIO₃ were added. Since this amount of KIO₃ would be sufficient to oxidize 25 mg of HFH to hematein we have termed this half-oxidized hematoxylin (HOH). The peak absorbance (560 nm) of this purple solution remained constant for at least a week. With omission of the KIO₃ the solution was colorless. A curve was constructed by plotting absorbance against concentration of hematein in HOH at various dilutions. For analyses of hematein content of commercial hematoxylins 50 mg of sample and 100 mg of hydroquinone were dissolved in 5 ml of ethylene glycol and then 45 ml of a 5% solution of KAl(SO₄)₂. 12H₂O were added. The addition of the hydroquinone stabilized the absorbance for about 5 min. The hematein content could then be calculated by comparing the observed absorbance with the standard curve. Eleven samples of hematoxylin certified by the Biological Stain Commission had hematein concentrations varying from 0.01 to 0.43%. For analyses of the available hematein content of commercial hemateins, 50 mg of sample were dissolved in 10 ml of ethylene glycol, then 45 ml of water and 45 ml of 5% KAI(SO₄)₂. 12H₂O added. The hematein content could then be calculated by comparing the observed absorbance with the standard curve. In 9 samples of hematein from 4 different sources the active hematein content varied from 19 to 97%.     

Water soluble platinum(II) and palladium(II) complexes of alkyl sulfonated phosphines

The reactions of the alkylsulfonated phosphines LM=Ph₂P(CH₂)_nSO₃Na/K (n=2, 3, 4) with K₂PtCl₄ and K₂PdCl₄ have been studied in homogeneous aqueous solution as a function of pH. In homogeneous acidic solution the protonated phosphines react to give cis- and trans-PtCl₂(LH)₂. The biphasic reaction between 1,5-cyclooctadiene platinum(II) chloride in dichloromethane and acidified aqueous LNa/K gives a higher proportion of the cis isomer. In neutral solution the initial reaction to give [PtCl(LNa/K)₃]⁺Cl⁻ is followed by slow formation of cis-PtCl₂(LNa/K)₂. K₂PdCl₄ reacts more rapidly to give PdCl₂(LNa/K)₂. In homogeneous alkaline solution rapid oxidation of the phosphine occurs with only small amounts of platinum complex being observable. The biphasic reaction yields phosphine oxide in the aqueous layer and a small amount of the chelate complexes PtL₂ in the organic. Representative complexes have been isolated and characterised and the mechanisms for the reactions discussed. The electrospray mass spectra of solutions of the isolated complexes have been recorded in both positive and negative ionisation modes. The positive ionisation spectra are complicated, but platinum and palladium containing ions derived from loss of chloride, H⁺ and HCl are observed in the negative ionisation spectra.     

Syntheses and characterization of copper complexes with the ligand 2-aminoethyl(2-pyridylmethyl)-1,2-ethanediamine (apme)

Copper(I)/(II) complexes with the ligand 2-aminoethyl(2-pyridylmethyl)1,2-ethanediamine (apme, abbreviated as PDT in the literature as well) were prepared and characterized. Crystal structures of the copper(I) complexes, [Cu₂(apme)₂]X₂ (1, 2; X = ClO₄, CF₃SO₃), showed that they are dinuclear, in contrast to the trigonal bipyramidal copper(II) complexes [Cu(apme)Cl]BPh₄ (3) and [Cu(apme)(DMF)](BPh₄)₂ (4). 1 and 2 could be investigated in solution by NMR spectroscopy and 3 and 4 by cyclovoltammetry. From the results of these studies it is clear that in solution equilibria between the dinuclear complexes 1/2 and another species exist, most likely the monomeric [Cu(apme)CH₃CN]⁺. Time-resolved UV/vis spectra at low temperatures allowed the spectroscopic detection of dioxygen adduct complexes as reactive intermediates during the oxidation of 1/2 with dioxygen that seem to play an important role in copper enzymes such as peptidylglycine--hydroxylating monooxygenase (PHM).     

The synthesis and reactivity of electrophilic iridium (III) complexes containing bis (diphenylphosphino) ethane

The complex Ir(CH₃) (CO) (CF₃SO₃)₂ (dppe) (1) has been synthesized from the reaction of Ir(CH₃)I₂(CO) (dppe) and silver triflate. Methane and IrH(CO) (CF₃SO₃)₂ (dppe) (2) are formed when a methylene chloride solution of 1 is placed under 760 torr dihydrogen. Conductivity studies indicate that methylene chloride solutions of complexes 1 and 2 are weak electrolytes and only partially ionized at concentrations above 1 mM. Complex 2 is an effective hydrogenation catalyst for ethylene and 1-hexene while acetone hydrogenation is inhibited by the formation of [IrH₂(HOCH(CH₃)₂) (CO) (dppe)] (OTf) (3). Linear dimerization and polymerization of styrene occurs via a carbocationic mechanism initiated by triflic acid elimination from 2. Treatment of an acetonitrile solution of Ir(CH₃)I₂(CO) (dppe) with silver hexafluorophosphate produces the solvent promoted carbonyl insertion product [Ir(C(O)CH₃) (NCCH₃)₃ (dppe)] [PF₆]₂ (7) which readily undergoes deinsertion in methylene chloride to form [Ir(CH₃) (CO) (NCCH₃)₂ (dppe)] [PF₆]₂ (8) and acetonitrile.     

Two new multi-cobalt-containing heteropolyoxotungstates

Two new multi-cobalt-containing polyoxotungstates K₄Na₆Co₂(H₂O)₁₂{Co(H₂O)₄[Co₂(H₂O)₁₀Co₄(H₂O)₂(B--SiW₉O₃₄)₂]₂} · 40H₂O (1) and K₁₀Na₂[Co₄(H₂O)₂(GeW₉O₃₄)₂] · 20H₂O (2) have been obtained by the routine synthetic reactions in aqueous solution. The polyoxoanion framework of 1 consists of two sandwich-type polyoxoanions [Co₄(H₂O)₂(B--SiW₉O₃₄)₂]¹²⁻ connected together by a [CoO₂(H₂O)₄] cluster to constitute the sandwich dimer, and then, four isolated Co(H₂O)₅ cations coordinate to the dimer through four μ₂-O atoms. The polyoxoanion 2 is isomorphic to the sandwich-type polyoxoanion [Co₄(H₂O)₂(B--SiW₉O₃₄)₂]¹²⁻ in 1. The magnetic property of compound 1 has been studied by measuring its magnetic susceptibility in the temperature range 2.0–300.0 K, indicating the existence of intramolecular ferromagnetic Co–Co interactions, and, the electrochemical properties of 1 and 2 are detected in the pH 4 buffer solution.     

Dissolution of [RhCl(PPh3)3] in the ionic liquid, 1-ethyl-3-methyl imidazolium chloroaluminate(III), and its reaction with H2. The stabilization of Rh(I) species in an ionic liquid

The solution of [RhCl(PPh₃)₃] in acidic 1-ethyl-3-methylimidazolium chloroaluminate(III) ionic liquid (AlCl₃ molar fraction, x_AlCl3=0.67) was investigated by ¹H and ³¹P{¹H} NMR. One triphenyl phosphine is lost from the complex and is protonated in the acidic media, and cis-[Rh(PPh₃)₂ClX], (2), where X is probably [AlCl₄]⁻, is formed. On, standing, 2 is converted to trans-[Rh(H)(PPh₃)₂X], (3). The reaction of 2 and H₂ also produces trans-[Rh(H)(PPh₃)₂X], (3). ¹H and ³¹P{¹H} NMR support the suggestion that a weak ligand such as [AlCl₄]⁻, present in solution may interact with the metal centre. When [RhCl(PPh₃)₃] is dissolved in CH₂Cl₂/AlCl₃/HCl for comparison, two exchanging isomers of what is probably [RhH{(μ-Cl)₂AlCl₂}{(μ-Cl)AlCl₃}(PPh₃)₂], (6) and (7), are formed.     

Synthesis, structure, and heterogeneous catalytic activity of tungsten chalcogenide cubane cluster containing alkaline earth metal complex

A new compound containing a cubane tungsten chalcogenide cluster [W₄(μ₃-Te)₄(CN)₁₂]⁶⁻ and Ca²⁺ complex units has been prepared by the reaction of aqueous solution of K₆[W₄(μ₃-Te)₄(CN)₁₂] · 5H₂O with the solution of a Ca(NO₃)₂ and phen(1,10-phenanthroline) (1:2 molar ratio) in a solvent mixture of H₂O/EtOH. The structure of [{Ca(phen)₂(H₂O)}{Ca(phen)(H₂O)₄}{Ca(phen)₂(H₂O)₃}][W₄Te₄(CN)₁₂] · 5H₂O 1 has been determined by X-ray crystallography. Compound 1 contains [{Ca(phen)(H₂O)₄}{Ca(phen)₂(H₂O)₃}][W₄(μ₃- Te)₄(CN)₁₂] units bridged by {Ca(phen)₂(H₂O)}²⁺ units to form an one-dimensional zigzag chain structure. Interestingly, compound 1 showed a heterogeneous catalytic activity in the transesterification of a range of esters with methanol under the mild conditions. Moreover, it can be reused without any loss of activity through 10 runs with ester.     

A Rapid Silver Impregnation Method for Nervous Tissue: A Modified Protargol-Peroxide Technic

A rapid, reliable silver impregnation method is described for nervous tissue fixed in formol-saline, Bouin or Sum. Sections are impregnated for 10-15 minutes at room temperature or 37 C in a solution containing 0.5 g Protargol-S, 0.005-0.01 g allantoin, 1 ml of 1% Cu[NO₂]₂, 1 ml of 1% AgNO₃. and 1-2 drops of 30% H₂O₂ in 100 ml distilled water. Thereafter the dons arc reduced in a hydroquinone-formalin solution. This is followed by gold toning and subsequent reduction and mounting. Alternatively. following the first reduction, the silver image can be intensified by placing sections in a silver-allantoin bath which is followed by reduction and mounting. This method is very reliable and selective, making it suitable for general routine and research use.     

树木气孔浸润级与SO2伤害及ABA的防护作用

以常见绿化树种为材料,通过实地测定和熏烟实验,探讨了气孔浸润级与树木SO₂伤害的关系及ABA的防护效应.结果表明,在特定环境下,相同树种的气孔浸润级较为稳定,不同树种的气孔浸润级差异较大;浸润级与叶绿素结合度呈负相关变化,但不明显;与K⁺渗出量呈正相关(r=0.92,α＜0.01),并按95%的置信度绘制了伤害预测图.不同SO₂浓度条件下,对同一树种的气孔浸润级的影响甚小,不超过一个等级,K⁺渗出量则依大气SO₂浓度和树木吸S量的增加而增多.气孔浸润级依ABA溶液处理浓度增大而降低,K⁺渗出量也相应减少,经2.5mol·L^-1×4h剂量的SO₂熏烟,预涂30mol·L^-1ABA者,降低了1.5～3个浸润级,K⁺渗出量减少36.5%～54.8%,其测定值与自然对照值相近,防护作用显著.     

外源H2O2对盐碱混合胁迫下裸燕麦幼苗生长和抗性生理的影响

为探讨信号分子过氧化氢（H₂O₂）增强裸燕麦盐碱耐性的作用及其生理机制,以裸燕麦品种‘定莜6号’为材料,在日光温室内用珍珠岩培养幼苗至三叶一心期时叶面喷施0.01 mmol·L^-1 H₂O₂的同时根部浇灌75 mmol·L^-1盐碱混合溶液（NaCl：Na₂SO₄：NaHCO₃：Na₂CO₃=12：8：9：1）或添加H₂O₂淬灭剂二甲基硫脲（DMTU）,研究对幼苗生长及叶片光合色素含量、活性氧代谢和渗透调节物质积累的影响。结果表明：喷施H₂O₂能够缓解盐碱混合胁迫对裸燕麦幼苗生长的抑制,提高幼苗根长、株高和植株干重及叶片叶绿素a、叶绿素b、总叶绿素、类胡萝卜素含量和超氧化物歧化酶、过氧化物酶、过氧化氢酶、抗坏血酸过氧化物酶活性,降低超氧阴离子、H₂O₂、丙二醛、抗坏血酸、谷胱甘肽和游离氨基酸含量,促进抗氧化物质类黄酮、总酚和原花青素及渗透调节物质可溶性蛋白质、可溶性糖和脯氨酸积累。添加DMTU部分或完全逆转了H₂O₂的上述作用。采用隶属函数综合评价显示,喷施H₂O₂提高了盐碱混合胁迫下裸燕麦幼苗的综合评价值D,添加DMTU完全逆转了H₂O₂对D值的提升作用。表明外源H₂O₂通过参与活性氧代谢和渗透调节物质积累等生理代谢调控缓解盐碱混合胁迫诱导的氧化伤害和生长抑制,从而提高裸燕麦对盐碱胁迫的适应能力。     

The Quantitative Determination of Osmium Tetroxide in Fixatives

This rapid spectrophotometric method for determining the OsO₄ concentration in fixative and stock solutions is based on the reduction of OsO₄ by acidified KI to the blue species of OsI₆ =, which is then determined at 649 mµ. The salt K₂OsI₆ has been isolated from the reaction mixture and characterized. Method: A I ml aliquot of the solution, containing up to 3% OsO₄, is diluted to 100 ml with distilled water. To 1 ml of the diluted solution is added, in order: distilled water, 2 ml; 1 M HCI, 1 ml; and 1 M KI, 1 ml. Optical density at 649 mµ is read from 10-120 min thereafter. OsO₄ concentration is calculated from the measured molecular extinction coefficient of OsI₆ =, 4400 liter/mole cm.     

The use of the borocaptate anion as a ligand. Synthesis and X-ray crystal structure of pentaammine (1-thiolato-closo-undecahydrododecaborane)ruthenium(III) dihydrate

The complex [Ru(SB₁₂H₁₁)(NH₃)₅]·2H₂O has been prepared by the reaction of Cs₂B₁₂H₁₁SH with [RuCl(NH₃)₅]Cl₂ in aqueous solution. The complex represents the first reported example of the borocaptate anion acting as a ligand. The structure of the complex has been determined by single crystal X-ray diffraction analysis. The crystal parameters are monoclinic, space group P2₁/c, A = 8.056(1), B = 14.240(2), C = 15.172(2) Å, β=98.48° and Z = 4. The ruthenium atom has a distorted octahedral coordination. The distortion is probably due to the high (3⁻) charge and the large bulk of the borocaptate ligand. These features can also be observed in the spectroscopic properties of the complex.     

Facile and stereoselective condensation of acetone with ammonia ligands on cobalt(III): structure of a N-bonded cyanate complex containing the 2-methyl-2-amino-4-imino-pentane ligand

The complex [(NH₃)₅CoO₃SCF₃](CF₃SO₃)₂ reacts with excess NaNCO in warm acetone solution to give, stereoselectively, a Schiff base complex (40%) which has been characterized by standard NMR techniques as one of the six isomers of [Co{NH₂C(CH₃)₂CH₂C(CH₃)=NH}₂(NH₃)NCO](ClO₄)₂ · H₂O, confirmed by a single crystal X-ray structural analysis. Schiff base formation in non-basic conditions for kinetically inert Co(III) complexes is unprecedented. Also, this is only the second cyanate complex of pentaaminecobalt(III) to be structurally characterized (CoNCO: Co–N, 1.908 Å; N–C, 1.152 Å; C–O, 1.206 Å; Co–N–C, 170°; N–C–O, 177°).     

Degradation activity of adhered and suspended Pseudomonas cells cultured on 2,4,6-trichlorophenol, measured by indirect conductimetry

The degradation activity (expressed as specific CO₂ production rates) of adhered and suspended Pseudomonas cells, strains SP1 and SP2, during the degradation of 2,4,6-trichlorophenol (2,4,6-TCP), was compared using indirect conductimetry technique. This technique is defined as the measurement of CO₂ ionization in an alkaline solution and expressed as the negative conductance change values of such solution. The attachment surfaces were porous glass and silicone rubber. The 2,4,6-TCP concentrations ranged from 10 to 500 mg 1⁻¹. Specific respiration rates were determined from CO₂ evolution rates and biomass yields of both suspended and adhered cell cultures. CO₂ evolution rates were determined after conversion of conductance change values into CO₂ produced values. Results indicate that glass-adhered cells reached a higher maximum specific CO₂ evolution rate ( Q _CO2max) than both suspended and silicone rubber-adhered cells. However, suspended cells showed a lower saturation constant ( K_s ) than the adhered cells. These results suggest that depending on support nature the respiration activity of adhered cells could be higher than of suspended cells. Moreover, the indirect conductimetry technique could efficiently be used by measurements of respiration activities of both attached or suspended xenobiotic-degrading micro-organisms.     

A precise potentiometric method for determination of algal activity in an open CO2 system

Abstract. The activity of the green alga Scenedesmus obliquus was studied in simplified nutrient solutions (20 mol m₋₃ NaNO₃, 20 mol m₋₃ NH₄C1, 20 mol m₋₃ NH₄NO₃, and 20 mol m₋₃ NaCl, respectively) at 25 °C. The experiments were performed under welldefined incident photon density fluxes ranging from 10 to 200 μmol m₂ s₋₁, Light-dependent changes in pH and alkalinity (A) were followed by means of a potentiometric method using a glass electrode. In the experiments, carbon dioxide with known partial pressure was bubbled through the algal suspension, and during dark periods ul intervals of 1 h, the solution was allowed to equilibrate with the gas phase. This technique was applied to calculate equilibrium values of pH and alkalinity at regular intervals during a 12-h period. Results obtained in NaNO₃, solution show a linear increase in A with time, at each level of illumination studied. After an initial drop, A also increases in NH₄NO₃, solution in a similar way to that in NaNO₃ solution. The change in A with time was also found to increase linearly with the photon density flux studied and no saturation level could be defined. In experiments in NaCl solution, no changes in A were registered while measurements in NH₄Cl solution showed a decrease in A with time.     

The stereochemistry of Co(III)-amine complexes. The use of nOe and COSY H NMR spectroscopy to determine structure in solution

It is shown how 1D nOe and 2D COSY ¹H NMR spectroscopy can be used to assign the stereochemistry of Co(III) amine complexes. By using d₆-DMSO as solvent together with a small quantity of DCl all non-equivalent N---H hydrogens can be distinguished at 300 MHz. Through-space (nOe), and through-bond (COSY), associations with other N---H and C---H hydrogens can then be determined. This leads to a complete assignment of structure in solution. The technique is applied to the complexes syn(N), anti(N)-[Co(cyclen) (NH₃)₂] (ClO₄)₃, syn(N), anti(Cl)-[Co(cyclen) (NH₃)Cl] (ClO₄)₂, anti(N), syn(Cl)-[Co(cyclen) (NH₃)Cl](ClO₄)₂, syn(N), anti(O)-[Co(Mecyclen)-(GlyO)](ClO₄)₂ and Δ-cis-[Co(δ-en)₂(NO₂)₂](NO₂).