The concave-convexproperty of a surface is one of the important and classical issues in differential geometry.

曲面的凹凸是微分几何学中的经典问题之一,划分出曲面上不同的凹凸区域,对于研究曲面的凹凸以及其他性质是一件很有意义的工作。

This article present the continuity,differentiability,monotonicity,concave-convex,parity and periodicity of the function netermined by the definite integral of variable upper limit and variable lower limit,establishes the sufficient and necessary requirements of functional convex and integrability of derived function by using the definite integral of variable upper limit.

给出了变上限与变下限定积分所确定函数的连续性、可微性、单调性、凹凸性、奇偶性、周期性,利用变上限定积分建立了函数凸及导函数可积的充分必要条件。

Some definitions and discriminating methods have been given on the monotonicity,extreme value,concave-convexand inflection points of the curve r=r(θ).

研究了极坐标系中曲线r =r(θ)的切线、法线、渐近线方程 ,给出了r =r(θ)的单调性、极值、凹凸、拐点的定义和判别法 ,从而解决了《数学分析》中未曾解决的极坐标方程所表示的曲线的作图问

Remediation of attapulgite on copper contaminated soil;

凹凸棒石修复铜污染土壤

Character of attapulgite adsorbent and its application in oil bleaching;

凹凸棒石吸附剂特征及其在油脂脱色过程中的应用研究

Effect of PP-g-MAH on Mechanical Properties of PP/AttapulgiteComposites;

聚丙烯接枝马来酸酐对聚丙烯/凹凸棒石复合体系力学性能的影响

Adsorption properties of attapulgite clayand activated carbon to water-soluble dyes;

凹凸棒土与活性炭对水溶性染料的吸附研究

Bleaching of hemp seed oil with activated attapulgite clay;

活性凹凸棒土对大麻籽油脱色的研究

Study on the treatment of chromium contarining wastewater with modified attapulgite clay;

改性凹凸棒土净化含铬废水的研究

Study on the Ion exchange of potassium,calcium and magnesium by alter-attapulgite;

改性凹凸棒土对钾、钙、镁离子交换作用的研究

Preparation and characterization of nano TiO_2-attapulgitecomposites;

纳米TiO_2/凹凸棒土复合体的制备及其表征

Study on the simultaneous determination of Zn(Ⅱ) in food based on pre-separation/enrichment by attapulgitewith FAAS;

凹凸棒土预分离/富集与FAAS联用分析粮食中Zn(Ⅱ)的研究