An adjustable flow restrictor for implantable infusion pumps based on porous ceramics

2015 ◽  
Vol 60 (4) ◽  
Author(s):  
Holger Jannsen ◽  
Stephan Klein ◽  
Bodo Nestler
Keyword(s):  
Flow Rate ◽  
Path Length ◽  
Porous Ceramic ◽  
Porous Ceramics ◽  
Infusion Pumps ◽  
Long Term Stability ◽  
Adjustment Time ◽  
Flow Through ◽  
Flow Path Length

AbstractThis paper describes an adjustable flow restrictor for use in gas-driven implantable infusion pumps, which is based on the resistance of a flow through a porous ceramic material. The flow inside the walls of a ceramic tube can be adjusted between 270 nl/min and 1260 nl/min by changing the flow path length in the ceramic over a distance of 14 mm. The long-term stability of the flow restrictor has been analyzed. A drift of -8% from the nominal value was observed, which lies within the required tolerance of ±10% after 30 days. The average time needed to change the flow rate is 40 s. In addition, the maximum adjustment time was 110 s, which also lies within the specification.

The Evaluation of the PXQ for the Analysis of Cements and Related Materials

1958 ◽  
Vol 2 ◽  
pp. 215-227
Author(s):  
George Andermann ◽  
J. L. Jones ◽  
E. Davidson
Keyword(s):  
Flow Rate ◽  
Gas Flow ◽  
Applied Research ◽  
Production Control ◽  
Helium Flow ◽  
X Ray ◽  
Long Term Stability ◽  
Short And Long Term

AbstractThe analysis of cements and ores has been studied using the Applied Research Laboratories, Inc. Production Control X-ray Quantometer (PXQ), Elements included in the program were magnesium, aluminum, silicon, phosphorus, calcium and iron. The PXQ, utilizing the polychromator concept, allows the simultaneous determination of the listed elements.Focusing ADP, EDT, quartz and LiF crystals were used with flow Geigers or Multitrons. Helium paths were used as required. The choice of crystals, detectors, and slit widths was determined to give optimum results for each element.The effects of briquetting and ratioing to scattered background on accuracy were studied. Various instrumental factors such as helium flow rate, detector gas flow rate, short and long term stability were also investigated.

Treatment of Agricultural Wastewater Using Porous Ceramics Composite of Hydroxyapatite and Silica

2012 ◽  
Vol 622-623 ◽  
pp. 915-918 ◽  
Author(s):  
Supansa Intapong ◽  
Anirut Raksudjarit
Keyword(s):  
Porous Ceramic ◽  
Porous Ceramics ◽  
Ceramic Composites ◽  
Ceramic Filter ◽  
Water Filtration ◽  
Sintered Ceramic ◽  
Agricultural Wastewater ◽  
Flow Through ◽  
Silica Nanopowder

Porous ceramics filter was prepared by sintering of hydroxyapatite (HA) and silica composite nanopowder. Silica nanopowder of 50 wt% are incorporated into HA nanopowder. The mixing powders are uniaxially compact and then sintering at 900°C-1050°C in air. The characterization of the porous was carried out by scanning electron microscopy (SEM). Filtration studies using porous ceramic were performed for agricultural wastewater. The studies of the water filtration and flow through these porous showed that the sintered ceramic filter at all temperatures reduced the TDS, TS, conductivity, and arsenic (As) content. The water permeated through porous ceramic composites could be compared to drinking water quality.

Highly effective catalytic reduction of nitrobenzene compounds with gold nanoparticle-immobilized hydroxyapatite nanowire-sintered porous ceramic beads

2021 ◽  
Vol 45 (10) ◽  
pp. 4601-4610
Author(s):  
Jie Li ◽  
Minjie Wu ◽  
Hongchen Du ◽  
Buchuan Wang ◽  
Yinglong Li ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Gold Nanoparticle ◽  
Catalytic Reduction ◽  
Porous Ceramic ◽  
High Catalytic Activity ◽  
Term Stability ◽  
Long Term Stability ◽  
Highly Effective ◽  
Porous Channels

A catalytic ceramic bead with micron-sized and interconnected porous channels, adjustable porosity, high catalytic activity, and long-term stability is prepared.

Stability and Change in Emotional Intelligence: Exploring the Transition to Young Adulthood

2005 ◽  
Vol 26 (2) ◽  
pp. 100-106 ◽  
Author(s):  
James D.A. Parker ◽  
Donald H. Saklofske ◽  
Laura M. Wood ◽  
Jennifer M. Eastabrook ◽  
Robyn N. Taylor
Keyword(s):  
High School ◽  
Emotional Intelligence ◽  
Postsecondary Education ◽  
Life Transition ◽  
Full Time ◽  
Major Life ◽  
Long Term Stability ◽  
Time Period ◽  
Transition From High School

Abstract. The concept of emotional intelligence (EI) has attracted growing interest from researchers working in various fields. The present study examined the long-term stability (32 months) of EI-related abilities over the course of a major life transition (the transition from high school to university). During the first week of full-time study, a large group of undergraduates completed the EQ-i:Short; 32 months later a random subset of these students (N = 238), who had started their postsecondary education within 24 months of graduating from high school, completed the measures for a second time. The study found EI scores to be relatively stable over the 32-month time period. EI scores were also found to be significantly higher at Time 2; the overall pattern of change in EI-levels was more than can be attributed to the increased age of the participants.

Multi-Center Calibration of the Second Reference Material for Thromboplastin, Rabbit, Plain, Coded CRM 149R

1991 ◽  
Vol 65 (03) ◽  
pp. 263-267 ◽  
Author(s):  
A M H P van den Besselaar ◽  
R M Bertina
Keyword(s):  
Reference Material ◽  
Standard Error ◽  
Standard Errors ◽  
Sensitivity Index ◽  
Long Term Stability ◽  
Significant Bias ◽  
The Mean ◽  
The Relationship ◽  
International Sensitivity Index

SummaryIn a collaborative trial of eleven laboratories which was performed mainly within the framework of the European Community Bureau of Reference (BCR), a second reference material for thromboplastin, rabbit, plain, was calibrated against its predecessor RBT/79. This second reference material (coded CRM 149R) has a mean International Sensitivity Index (ISI) of 1.343 with a standard error of the mean of 0.035. The standard error of the ISI was determined by combination of the standard errors of the ISI of RBT/79 and the slope of the calibration line in this trial.The BCR reference material for thromboplastin, human, plain (coded BCT/099) was also included in this trial for assessment of the long-term stability of the relationship with RBT/79. The results indicated that this relationship has not changed over a period of 8 years. The interlaboratory variation of the slope of the relationship between CRM 149R and RBT/79 was significantly lower than the variation of the slope of the relationship between BCT/099 and RBT/79. In addition to the manual technique, a semi-automatic coagulometer according to Schnitger & Gross was used to determine prothrombin times with CRM 149R. The mean ISI of CRM 149R was not affected by replacement of the manual technique by this particular coagulometer.Two lyophilized plasmas were included in this trial. The mean slope of relationship between RBT/79 and CRM 149R based on the two lyophilized plasmas was the same as the corresponding slope based on fresh plasmas. Tlowever, the mean slope of relationship between RBT/79 and BCT/099 based on the two lyophilized plasmas was 4.9% higher than the mean slope based on fresh plasmas. Thus, the use of these lyophilized plasmas induced a small but significant bias in the slope of relationship between these thromboplastins of different species.

The Stability of the WHO Reference Thromboplastin NIBS & C 67/40

1979 ◽  
Vol 42 (04) ◽  
pp. 1135-1140 ◽  
Author(s):  
G I C Ingram
Keyword(s):  
Human Brain ◽  
Collaborative Study ◽  
Calibration Constant ◽  
Long Term Stability ◽  
Freeze Dried ◽  
Show Evidence ◽  
Human Material ◽  
Reference Preparation ◽  
The Stability

SummaryThe International Reference Preparation of human brain thromboplastin coded 67/40 has been thought to show evidence of instability. The evidence is discussed and is not thought to be strong; but it is suggested that it would be wise to replace 67/40 with a new preparation of human brain, both for this reason and because 67/40 is in a form (like Thrombotest) in which few workers seem to use human brain. A �plain� preparation would be more appropriate; and a freeze-dried sample of BCT is recommended as the successor preparation. The opportunity should be taken also to replace the corresponding ox and rabbit preparations. In the collaborative study which would be required it would then be desirable to test in parallel the three old and the three new preparations. The relative sensitivities of the old preparations could be compared with those found in earlier studies to obtain further evidence on the stability of 67/40; if stability were confirmed, the new preparations should be calibrated against it, but if not, the new human material should receive a calibration constant of 1.0 and the new ox and rabbit materials calibrated against that.The types of evidence available for monitoring the long-term stability of a thromboplastin are discussed.

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