Process engineering approach to large-volume methacrylate monolith synthesis for plasmid purification

The construction of large?volume methacrylate monolithic columns for preparative-scale plasmid purification is obstructed by the enormous release of exotherms, thus introducing structural heterogeneity in the monolith pore system. A remarkable radial temperature gradient develops along the monolith thickness, reaching a terminal temperature that supersedes the maximum temperature required for the preparation of a structurally homogeneous monolith. A novel heat expulsion technique is employed to overcome the heat build-up during the synthesis process. The enormous heat build-up is perceived to encompass the heat associated with initiator decomposition and the heat released from free radical-monomer and monomer-monomer interactions. The heat resulting from the initiator decomposition was expelled along with some gaseous fumes before commencing polymerisation in a gradual addition fashion. Characteristics of a 50 mL monolith synthesized using this technique showed an improved uniformity in the pore structure radially along the length on the monolith. Chromatographic characterization of this adsorbent displayed a persistent binding capacity of 14.5 mg pDNA/mL of the adsorbent. The adsorbent was able to fractionate a clarified bacteria lysate in only 3 min (after loading) into RNA, protein and pDNA respectively. The pDNA fraction obtained was analyzed to be a homogeneous supercoiled pDNA.

Technical quality

Close attention to technical quality or image optimization in transthoracic echocardiography (TTE) is important for the acquisition of high-quality diagnostic images and to ensure that measurements are accurately performed. For this purpose, the echocardiographer must be familiar with all the controls on the ultrasound machine that can be manipulated to optimize the two-dimensional (2D) images, color Doppler images, and spectral Doppler traces...

Solis-Cohen family papers, 1808-1990.

Correspondence, diaries, acount books, pamphlets, and other personal and professional materials pertaining to Jacob da Silva Solis and his descendents.

American Jewish Committee. Office of Jewish War Records, undated, 1918-1921, 1962.

The records consist of documentation of the American Jewish Committee's project to describe Jewish participation in the United States Armed Forces during World War I. The bulk of the material consists of questionnaires that the AJC sent to servicemen to determine Jewish identity, which contain information on personal identification and details of military service. Responses to the questionnaire come from both Jews and non-Jews. In addition, the collection contains office papers concerning the project and a ledger of manuscripts. The manuscripts document the distribution of records the Office of Jewish War Records collected, as well as list Jews who died or were given military honors.

Pennsylvania Packet and Daily Advertiser. Containing anecdote regarding Oliver Cromwell and the Jew

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Seixas family registers

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Letter from Manuel Josephson to Moses Seixas, February 4, 1890

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Letter of recommendation for Jacques Judah Lyons from Isaac Leeser

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Letter of Anne Seixas acknowledging $200 allowance

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Letter from D. G. Seixas to M. L. M. Peixotto regarding Hebrew name of Mr. Solomons

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Order to pay Aaron Levy, regarding K. K. Mikve Israel

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Letter from Isaac Seixas to Hayman Levy on proposed marriage of Benjamin Seixas to Zipporah Levy

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Ketubah of Sabato Morais and Esther Weil

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Grid interfacing of a photovoltaic system using a chain cell converter

With the rapid development of photovoltaic system installations and increased number of grid connected power systems, it has become imperative to develop an efficient grid interfacing instrumentation suitable for photovoltaic systems ensuring maximum power transfer. The losses in the power converter play an important role in the overall efficiency of a PV system. Chain cell converter is considered to be efficient as compared to PWM converters due to lower switching losses, modularized circuit layout, reduced voltage rating of the converter switches, reduced EMI. The structure of separate dc sources in chain cell converter is well suited for photovoltaic systems as there will b several separate PV modules in the PV array which can act as an individual dc source. In this work, a single phase multilevel chain cell converter is used to interface the photovoltaic array to a single phase grid at a frequency of 50Hz. Control algorithms are developed for efficient interfacing of the PV system with grid and isolating the PV system from grid under faulty conditions. Digital signal processor TMS320F 2812 is used to implement the control algorithms developed and for the generation of other control signals.