Simultaneous analysis of citrulline and arginine in serum and tissue

We developed a method for simultaneously determining l-citrulline and l-arginine levels in serum and tissue samples using RP-HPLC with ultraviolet (UV) detection. The serum was deproteinized by trichloroacetic acid and heat; the tissue was homogenized by trichloroacetic acid and deproteinized as the same as serum. Phenyl-isothiocyanate (PITC) solution was used as derivatization reagent and a gradient elution was carried out. The linearity for l-arginine and l-citrulline ranged from 0 to at least 1000 μmol/L. R² values were above 0.9999 for both. LODs for l-arginine and l-citrulline were 0.0462 μmol/L and 0.0195 μmol/L, respectively, while LOQs were 0.530 μmol/L and 0.417 μmol/L, respectively. Intra- and inter-day CVs were less than 3.5% and 7.5% in serum, respectively. The average recovery was from 85.5% to 116.5% in serum. Intra-assay CVs were 3.8% and 10.3%, and inter-assay CVs were 13.7% and 10.7% for l-arginine and l-citrulline respectively in tissue. The average recovery was from 92.8% to 113.5% in tissue. This is a reliable and convenient analytical method which is suitable for most clinical laboratories.     

Synthesis and Characterization of a Homochrial Manganese（Ⅱ）Complex Constructed from （1R,2R）-（-）-Diaminocyclohexane-N,N biscarboxyl-salicylidene）

A homochrial manganese(Ⅱ) complex derived from chiral salen ligand (1R,2R)-(-)diaminocyclohexane-N,N-biscarboxyl-salicylidene) (1) has been synthesized through solvothermal procedure and characterized by IR,elemental analysis,TGA,circular dichroism (CD),powder and single-crystal X-ray crystallography.It crystallizes in monoclinic,space group C2 with a=32.987(7),b=7.4662(15),c=17.931(4),β=97.82(3)°,V=4375.0(15) 3,Z=8,D c=1.544 g/cm 3,F(000)=2096,M r=508.36,μ=0.658 mm-1,the final GOOF=0.975,R=0.0676 and wR=0.2068 for 6357 observed reflections with I > 2σ(Ⅰ).The coordination polymer 1 possesses a 1D infinite zigzag chain architecture constructed by the dicarboxyl-functionalized metallosalen ligand (MnSalen),and the polymeric chains are further assembled into a 2D supramolecular network structure via strong intermolecular hydrogen bonding interactions between the adjacent zigzag chains.     

苯磺酰胺嘧啶类化合物的合成及其除草活性

在吡啶溶剂中,取代嘧啶胺与(取代)苯磺酰氯反应.合成了6个苯磺酰胺嘧啶类化合物(3a～3f),其结构经1H NMR和元素分析表征.初步的生物活性测试结果表明,3a～3f均具有一定的除草活性.     

Synthesis,structure and photoluminescence of two porous metal-organoboron frameworks with rtl topology

Rigid trigonal tris(3-pyridylduryl)borane L was synthesized through four steps in good overall yield from readily available 1,2,4,5-tetramethylbenzene and was used to construct two porous cadmium(II) complexes Cd(L)X2.G(X = Cl,Br;G = guset molecules),1(Cd(L)Cl2.EtOH.iPrOH.3H2O) and 2(Cd(L)Br2.MeOH.C7H8.3H2O),under mild reaction conditions.1 and 2 are isostructural and featured with 3D porous metal-organoboron framewoks with rtl topology,in which L acts as a 3-connected node while a dicadmium motif serves as...     

基于特殊路径的局内车辆路径问题混合策略研究

针对运输途中遇到的某一或一系列无法预知的堵塞事件对决策者路径选择策略的影响,考虑堵塞只发生在一条特殊路径上且可恢复的情况,采用局内竞争分析的思想,建立了局内车辆路径问题的数学模型,对车辆到达堵塞点时堵塞恢复时间未知这一情形下的路径选择问题,提出了两种混合策略,给出了相应的竞争比,并对其竞争性能进行了理论分析。     

刚竹毒蛾危害下的毛竹叶片光谱特征及虫害等级检测研究

探讨刚竹毒蛾危害下的毛竹叶片光谱特征可为建立竹林生态安全监测体系提供重要的理论指导。相比于传统的多光谱数据,高光谱遥感能够准确探测不同刚竹毒蛾危害等级间寄主光谱的细微变化。然而,当前有关此方面的研究甚少,其寄主的光谱变化机理还有待进一步总结。为此,基于实测的552条竹叶光谱,分析了健康、受刚竹毒蛾危害、小年叶片之间的光谱差异,选择可反映其健康状况的特征变量,并利用XGBoost模型建立了叶片尺度的刚竹毒蛾危害检测模型。研究结果显示：（1）随着虫害等级的上升,受害叶片在可见光范围内的反射率逐渐出现“绿低红高”的特征,其近红外波段的反射率则不断降低,而短波红外的反射率则明显高于健康叶片,尤其在两个水汽吸收波段（1 450和1 940 nm）的差异最为明显;（2）小年叶片于可见光-近红外波段的反射率显著高于健康、受害叶片;（3）根据不同受害类型叶片的光谱特征可知,较之健康叶片,缺刻型叶片的光谱并未出现太大的变化,红褐色病斑型叶片在红光波段的反射率出现了一定程度的上升,灰白色病斑型叶片则已经完全失去了植被的基本光谱特征;（4）根据XGBoost模型给出的变量重要性排序可知,各特征变量的贡献度依次为PRI（光化学反射率指数）＞FDVI_{576, 717}（植被健康程度评估指数）＞NPCI（归一化色素叶绿素指数）＞DSWI（疾病水胁迫指数）＞VOG 1（红边指数1）＞RVSI（红边植被胁迫指数）＞NDWI（归一化差值水分指数）;（5）模型对刚竹毒蛾危害识别的总平均精度为74.39%,其中健康叶片的识别精度达到了94.55%,轻度危害叶片为74.93%,重度危害为84.12%,小年叶片则为71.10%,而中度危害叶片的识别精度较差,仅为33.48%。     

液相体系中工艺条件对纳米碳酸钙晶形及聚集态的影响

对液相中形成纳米碳酸钙所加的分散剂和晶型控制剂，温度、浓度和搅拌速度等对晶形及聚集态的影响作了初步的研究，在反应温度8～15℃，反应物浓度0.1～0.4mol/L，搅拌速度3～20r/s，反应物加料时间4～12min的工艺条件下，可制备出粒径约50nm的高分散纳米碳酸钙，所控条件和相应的产品结果较令人满意。     

Semiclassical Method to Schroedinger Equation with Position-Dependent Effective Mass

In this paper, two novel semiclassical methods including the standard and supersymmetric WKB quantization conditions are suggested to discuss the Schroedinger equation with position-dependent effective mass. From a proper coordinate transformation, the formalism of the Schroedinger equation with position-dependent effective mass is mapped into isospectral one with constant mass and therefore for a given mass distribution and physical potential function the bound state energy spectrum can be determined easily by above method associated with a simple integral formula. It is shown that our method can give the analytical results for some exactly-solvable quantum systems.     

图的不可收缩性和end-正则性

图的半群理论是图的群理论的延伸．图的不可收缩性和end－正则性是其中受到普遍关注的课题．本文揭示了两者之间的内在联系．     

苯甲酸及其一氯代衍生物与邻菲罗啉或联吡啶的稀土铕三元配合物的荧光性质

本文报道合成了八种苯甲酸及其一氯代衍生物与邻菲罗啉或联吡啶的稀土铕三元配合物并测得了荧光光谱。通过改变第一和第二配体,研究了配合物发光峰强度、位置和分裂间隔等的变化情况,依据荧光发射峰的分裂推断出Eu~(3 )离子所处的局域环境对称性大致都是C_1,C_2或C_s。虽然配合物的局域对称性大致相同,但由于配体场作用和能级匹配等原因,发光峰位置和强度是不同的;讨论了第一配体分子结构的变化对荧光性能的影响,认为分子自身结构的对称性可能对提高配合物发光性能有较大影响;实验还观察到第二配体也参与配位且对发光性能影响较大。同时看到发光峰的分裂间隔大小变化和发光峰的相对强度的变化是一致的。