公开(公告)号：US4668864A

公开(公告)日：1987-05-26

申请号：US643280

申请日：1984-08-22

Applicant: Sahba Ghaderi ,  Duane P. Littlejohn

Inventor： Sahba Ghaderi ,  Duane P. Littlejohn

IPC: G01N27/62 ,  H01J49/36 ,  H01J49/38 ,  H01J49/14

CPC classification number: H01J49/38 ,  Y10S505/879

Abstract: A mass spectrometer of the type wherein a solenoidal magnet produces a magnetic field that includes a region along its geometric central axis. That region is a region of high field intensity and high homogeneity with magnetic flux lines in the region being generally parallel to the magnet central axis. A high vacuum is established in the region and a sample cell is positioned at or within the region in which sample ions are formed, trapped, excited and detected. An ionizing device is positioned outside of the region and off the central axis while an additional ionizing device may be positioned on the central axis. In a preferred embodiment, the off axis ionizing device may be supported for movement relative to the central axis. A preferred ionizing device for the off axis device is an electron gun.

Abstract translation: 一种质谱仪，其中螺线管磁体产生包括沿其几何中心轴线的区域的磁场。 该区域是高磁场强度的区域，并且该区域中的磁通线大体上平行于磁体中心轴具有高均匀性。 在该区域中建立高真空度，并且样品池位于样品离子形成，捕获，激发和检测的区域内或其内。 电离装置位于该区域的外部并且离开中心轴线，而另外的电离装置可以位于中心轴线上。 在优选实施例中，离轴电离装置可被支撑为相对于中心轴线移动。 用于离轴装置的优选电离装置是电子枪。

公开(公告)号：US06608304B1

公开(公告)日：2003-08-19

申请号：US09676819

申请日：2000-10-02

Applicant: Duane P. Littlejohn ,  Thomas Knudsen

Inventor： Duane P. Littlejohn ,  Thomas Knudsen

IPC: H01J4940

CPC classification number: H01J41/12

Abstract: A mass spectrometer (MS) which uses the Fourier transform ion cyclotron resonance (FTICR) technique to determine the mass of ions. The MS is prepared with a surface that guarantees that a particle striking the surface will have at least one contact with the cathode and will most likely be re-pumped before escaping into the vacuum chamber volume.

Abstract translation: 使用傅里叶变换离子回旋共振（FTICR）技术的质谱仪（MS）来确定离子的质量。 MS制备具有表面的表面，该表面保证撞击表面的颗粒将与阴极具有至少一个接触，并且最有可能在逸出到真空室体积之前被再次抽吸。

公开(公告)号：US06355929B1

公开(公告)日：2002-03-12

申请号：US09173889

申请日：1998-10-16

Applicant: Duane P. Littlejohn ,  W. Peter Schubert

Inventor： Duane P. Littlejohn ,  W. Peter Schubert

IPC: B01D5944

CPC classification number: F16K25/005 ,  F16K51/02

Abstract: A method for forming the seat in a pulsed sampling valve used in a FTICR MS. The valve has a ceramic ball that closes against the seat to thereby seal the passageway that is used for introduction of sample into the FTICR MS vacuum chamber. The material from which the seat is formed is chosen to withstand relatively high operating temperatures and a precise deburred hole is drilled in that material. The pre-load spring exerts a force against the ball when the valve is assembled. The force initially exceeds the yield strength of the seat material to deform the material to form the seat.

Abstract translation: 一种用于在FTICR MS中使用的脉冲采样阀中形成座椅的方法。 该阀具有一个陶瓷球，该陶瓷球靠在座上，从而密封用于将样品引入FTICR MS真空室中的通道。 选择形成座椅的材料被选择以承受相对高的操作温度，并在该材料中钻出精确的去毛刺孔。 当组装阀时，预加载弹簧对球施加力。 该力最初超过座椅材料的屈服强度以使材料变形以形成座椅。

公开(公告)号：US5233190A

公开(公告)日：1993-08-03

申请号：US797462

申请日：1991-11-22

Applicant: Fritz H. Schlereth ,  Duane P. Littlejohn ,  James E. Phillips

Inventor： Fritz H. Schlereth ,  Duane P. Littlejohn ,  James E. Phillips

IPC: G01R33/64 ,  H01J49/38

CPC classification number: G01R33/64 ,  H01J49/38

Abstract: A molecular spectrometer is provided that performs Fourier analysis utilizing the discrete Fourier Transform on a digitized time domain waveform that relates to the composition of a sample. Digitized reference waveforms are employed to permit the instrument to limit its analysis to frequencies of interest and thereby increase the rapidity of the analysis. Data at differing frequencies can be resolved at independent resolutions, and the instrument can analyze spectroscopic data in real time.

Abstract translation: 提供了一种分子光谱仪，其利用与样品组成相关的数字化时域波形上的离散傅里叶变换进行傅立叶分析。 数字化参考波形用于允许仪器将其分析限制到感兴趣的频率，从而增加分析的快速性。 不同频率的数据可以独立分辨率解析，仪器可以实时分析光谱数据。

公开(公告)号：US06498344B1

公开(公告)日：2002-12-24

申请号：US09676822

申请日：2000-10-02

Applicant: Duane P. Littlejohn

Inventor： Duane P. Littlejohn

IPC: H01J4924

CPC classification number: H01J41/18 ,  H01J49/24

Abstract: A mass spectrometer (MS) which uses the Fourier transform ion cyclotron resonance (FTICR) technique to determine the mass of ions. The MS is prepared with a surface that guarantees that a particle striking the surface will have at least one contact with the cathode and will most likely be re-pumped before escaping into the vacuum chamber volume.

Abstract translation: 使用傅里叶变换离子回旋共振（FTICR）技术的质谱仪（MS）来确定离子的质量。 MS制备具有表面的表面，该表面保证撞击表面的颗粒将与阴极具有至少一个接触，并且最有可能在逸出到真空室体积之前被再次抽吸。

公开(公告)号：US06232599B1

公开(公告)日：2001-05-15

申请号：US09173944

申请日：1998-10-16

Applicant: Duane P. Littlejohn

Inventor： Duane P. Littlejohn

IPC: B01D5944

CPC classification number: H01J49/38 ,  H01J41/12 ,  H01J49/0495

Abstract: A relay control for an ion pump used in a FTICR MS. When it is desired to admit new sample gas into the vacuum system, the high voltage that powers the ion pump is removed from the pump electrode by opening the normally closed relay contact. A normally open contact relay contact is then closed to ground the pump electrode and discharge any stray capacity. The sample valve is opened momentarily to admit new sample gas and after the ions are formed and trapped in the ion cell in the vacuum system the pump is restarted.

Abstract translation: 用于FTICR MS中的离子泵的继电器控制。 当希望将新的样品气体进入真空系统时，通过打开常闭继电器触点，从泵电极去除离子泵供电的高电压。 然后将常开触点继电器触点闭合以将泵电极接地并排出任何杂散电容。 样品阀瞬间打开以允许新的样品气体，并且在离子形成并被捕获在真空系统中的离子电池中之后，泵重新启动。

公开(公告)号：US6121609A

公开(公告)日：2000-09-19

申请号：US173913

申请日：1998-10-16

Applicant: Duane P. Littlejohn

Inventor： Duane P. Littlejohn

IPC: F16K31/06 ,  H01J49/04 ,  B01D59/44 ,  H01J49/00

CPC classification number: F16K31/0693 ,  F16K31/0675 ,  H01J49/0495

Abstract: The closure of a leak valve in a pulsed mass spectrometer is controlled to thereby substantially extend the life of the valve. An actuator responds to a pulse to open the valve. At the end of the open period the element that closes the valve seat is allowed to travel a substantial distance from the open position of the element to the nearly closed position of the element. The pulse amplitude is then controlled so that the time for the element to travel the remaining distance to valve seat closure is extended in time. The pulse amplitude can also be controlled so that the valve will never close except under fault conditions where power is lost or in a non-operating mode.

Abstract translation: 控制脉冲质谱仪中的泄漏阀的闭合，从而基本上延长阀的寿命。 致动器响应脉冲以打开阀门。 在打开期间结束时，关闭阀座的元件允许从元件的打开位置到元件的几乎闭合位置行进相当长的距离。 然后控制脉冲幅度，使得元件行进到阀座关闭的剩余距离的时间在时间​​上延长。 也可以控制脉冲幅度，使阀门永远不会关闭，除非在功率损耗或非工作模式下的故障条件下。

公开(公告)号：US4588888A

公开(公告)日：1986-05-13

申请号：US700298

申请日：1985-02-11

Applicant: Sahba Ghaderi ,  Juda L. Shohet ,  Duane P. Littlejohn

Inventor： Sahba Ghaderi ,  Juda L. Shohet ,  Duane P. Littlejohn

IPC: G01N27/62 ,  H01J49/38

CPC classification number: H01J49/38 ,  Y10S505/88

Abstract: A mass spectrometer of the type wherein the sample is ionized, excited into resonance and detected within a generally homogeneous magnetic field. During detection, the magnetic field is perturbed to form magnetic mirror regions to contain the ions. Prior to detection, the ions may be contained by conventional trapping techniques or by magnetic reflection.

Abstract translation: 这种类型的质谱仪其中样品被电离，激发成共振并在大致均匀的磁场内检测。 在检测期间，磁场被扰动以形成磁镜区域以容纳离子。 在检测之前，可以通过常规捕获技术或通过磁反射来包含离子。

公开(公告)号：US06255648B1

公开(公告)日：2001-07-03

申请号：US09173855

申请日：1998-10-16

Applicant: Duane P. Littlejohn ,  Robert W. Arnold

Inventor： Duane P. Littlejohn ,  Robert W. Arnold

IPC: B01D5944

CPC classification number: H01J49/147 ,  H01J49/022 ,  H01J49/38

Abstract: A quantity of electrons that will be used in the ionization event in an FTICR MS is preprogrammed. When the number of electrons produced reaches that number, the electron beam is turned off. This approach assures that the same number of electrons are used for every measurement and eliminates the variations due to fundamental characteristics of the electron sourcere and the variations in temperature due to changing ambient conditions.

Abstract translation: 将在FTICR MS中用于电离事件的电子量被预编程。 当产生的电子数达到该数时，电子束被关闭。 这种方法确保每次测量使用相同数量的电子，并消除由于电子源的基本特性和由于环境条件变化引起的温度变化引起的变化。

公开(公告)号：US06225624B1

公开(公告)日：2001-05-01

申请号：US09173910

申请日：1998-10-16

Applicant: Duane P. Littlejohn ,  Robert W. Arnold

Inventor： Duane P. Littlejohn ,  Robert W. Arnold

IPC: B01D5944

CPC classification number: H01J41/12 ,  H01J49/38

Abstract: During operation of a FTICR MS the time after the opening of the pulsed valve sample gas inlet system that the peak of sample gas pressure occurs in the vacuum chamber is determined by measuring the amplitude of the ion pump current. The FTICR MS then uses that time and the known period of time for which a source of electrons used for an ionization event is energized to energize the electron source so that the known period of time includes the peak of vacuum chamber sample gas pressure. This allows ions to be created during the peak of the sample gas pressure to thereby obtain the maximum sensitivity during measurements.

Abstract translation: 在FTICR MS的操作期间，通过测量离子泵电流的幅度来确定在脉冲阀样品气体入口系统打开样本气体压力的峰值在真空室中发生的时间。 然后，FTICR MS使用该时间和用于电离事件的电子源被激励以激励电子源的已知时间段，使得已知的时间段包括真空室样品气体压力的峰值。 这允许在样品气体压力的峰值期间产生离子，从而在测量期间获得最大灵敏度。