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公开(公告)号：US5368391A
公开(公告)日：1994-11-29
申请号：US979168
申请日：1992-11-18
IPC分类号： G01N21/76 , G01N5/04 , G01N25/00 , G01N25/20 , G01N25/48 , G06F17/10 , G06F17/14 , G01N25/18
CPC分类号： G01N5/04 , G01N25/4833
摘要： The present invention relates to analytical methods for determining the composition of a material that undergoes a transition as a function of a driving variable. As applied to thermogravimetric analysis (TGA), a first preferred embodiment comprises (1) decreasing the heating rate when deviations from a baseline signal are detected; (2) establishing a minimum heating rate; (3) forcing the heating rate to a predetermined maximum whenever the rate of change of the weight change with respect to the temperature falls below a predetermined value; and (4) adjusting the heating rate according to the rate of change of the weight of the sample to track a predetermined rate of change of the weight of the sample. A second preferred embodiment comprises (1) selecting either a high-productivity or a high-resolution mode; (2) in both modes, controlling the rate of temperature increase according to a function containing an exponential term, wherein the argument of the exponential term includes the percent weight change per unit time of the sample; (3) in the high-productivity mode, choosing the function so that when the percentage weight change per minute of the sample is small, the heating rate approaches the maximum allowed heating rate, and when the percentage weight change per minute is very large, the heating rate approaches zero; (4) in the high-resolution mode, choosing the function such that the heating rate is held at almost zero during a transition.
摘要翻译： 本发明涉及用于确定作为驱动变量的函数的经历转变的材料的组成的分析方法。 如应用于热重分析（TGA），第一优选实施方案包括（1）当检测到与基线信号的偏离时降低加热速率; （2）建立最低加热速率; （3）当重量变化率相对于温度降低到预定值以下时，强制加热速率达到预定最大值; 和（4）根据样品重量的变化率来调节加热速率以跟踪样品重量的预定变化率。 第二优选实施例包括（1）选择高生产率或高分辨率模式; （2），根据包含指数项的函数控制温度升高速率，其中指数项的自变量包括样本每单位时间的百分比重量变化; （3）在高生产率模式下，选择功能使得当样品的每分钟重量变化百分比小时，加热速率接近最大允许加热速率，当每分钟重量变化百分比非常大时， 加热速率接近零; （4）在高分辨率模式下，选择功能，使得转换期间加热速率保持在几乎为零。
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公开(公告)号：US5346306A
公开(公告)日：1994-09-13
申请号：US60214
申请日：1993-05-07
CPC分类号： G01N25/18 , G01N25/4833 , G01N25/4866
摘要： The present invention relates to differential analytical techniques for determining the composition, phase, structure, identification or other properties of a material that undergoes a transition as function of a driving variable. As applied to differential scanning calorimetric analysis (DSC), the preferred embodiment comprises: (1) heating a sample of the material with a linear temperature ramp that is modulated with a sinusoidal heating rate oscillation; and (2) deconvoluting the resultant heat flow signal into rapidly reversible and non-rapidly reversible components.
摘要翻译： 本发明涉及用于确定作为驱动变量的函数经历转变的材料的组成，相位，结构，识别或其它性质的差分分析技术。 如应用于差示扫描量热分析（DSC），优选实施方案包括：（1）用正弦加热速率振荡调制的线性温度斜坡加热材料样品; 和（2）将所得到的热流信号解卷积成快速可逆的和非快速可逆的分量。
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公开(公告)号：US5224775A
公开(公告)日：1993-07-06
申请号：US844448
申请日：1992-03-02
CPC分类号： G01N25/18 , G01N25/4833 , G01N25/4866
摘要： The present invention relates to differential analytical techniques for determining the composition, phase, structure, identification or other properties of a material that undergoes a transition as function of a driving variable. As applied to differential scanning calorimetric analysis (DSC), the preferred embodiment comprises: (1) heating a sample of the material with a linear temperature ramp that is modulated with a sinusoidal heating rate oscillation; and (2) deconvoluting the resultant heat flow signal into rapidly reversible and non-rapidly reversible components.
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公开(公告)号：US5165792A
公开(公告)日：1992-11-24
申请号：US663106
申请日：1991-03-01
CPC分类号： G01N5/04 , G01N25/4833
摘要： The present invention relates to analytical methods for determining the composition of a material that undergoes a transition as a function of a driving variable. As applied to thermogravimetric analysis (TGA), a first preferred embodiment comprises (1) decreasing the heating rate when deviations from a baseline signal are detected; (2) establishing a minimum heating rate; (3) forcing the heating rate to a predetermined maximum whenever the rate of change of the weight change with respect to the temperature falls below a predetermined value; and (4) adjusting the heating rate according to the rate of change of the weight of the sample to track a predetermined rate of change of the weight of the sample. A second preferred embodiment comprises (1) selecting either a high-productivity or a high-resolution mode; (2) in both modes, controllingn the rate of temperature increase according to a function containing an exponential term, wherein the argument of the exponential term includes the percent weight change per unit time of the sample; (3) in the high-productivity mode, choosing the function so that when the percentage weight change per minute of the sample is small, the heating rate approaches the maximum allowed heating rate, and when the percentage weight change per minute is very large, the heating rate approaches zero; (4) in the high-resolution mode, choosing the function such that the heating rate is held at almost zero during a transition.
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