Publications by authors named "Heinemann R"

Article Synopsis
  • A magnesium-aluminum layered double hydroxide (LDH) was created using a coprecipitation technique from a nitrate solution and transformed into a layered double oxide (LDO) after being heated to 450 °C.
  • During rehydration in a fluoride solution, the LDH's original structure was restored and fluoride ions were absorbed to maintain balance, a finding confirmed by energy-dispersive X-ray spectroscopy (EDS).
  • The study demonstrated that using ethanol during the rehydration process significantly increased fluoride incorporation, and the fluoride release pattern from the material revealed a rapid initial release followed by a slower, prolonged release.
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This article examines the concept of intelligence and giftedness of the German psychologist and philosopher William Stern, the leading intelligence and giftedness researcher in Germany from the early 20th century to 1933. Stern developed a multifactorial giftedness model that integrated empirical and philosophical perspectives and was thus far ahead of his time. This concept was not taken up for a long time-not least because of the break that the research on giftedness suffered in Germany in 1933-and has not yet been presented with the required complexity and interdisciplinarity.

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Silica particles were obtained from rice husk to which layered double hydroxide particles were deposited (weight ratio 1 : 1). Fe-Al layered double hydroxides (FeAl-LDH) were synthesized by co-precipitation with ratios Fe : Al of 3 : 1 in the presence of SiO particles from the rice husk. Characterization of the synthesized FeAl-LDH@SiO particles was performed by X-ray diffraction, Fourier transforms infrared spectroscopy (FTIR) and scanning electron microscopy with EDS.

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Carbon fibre reinforced polymer composites (CFRPs) can be costly to manufacture, but they are typically used anywhere a high strength-to-weight ratio and a high steadiness (rigidity) are needed in many industrial applications, particularly in aerospace. Drilling composites with a laser tends to be a feasible method since one of the composite phases is often in the form of a polymer, and polymers in general have a very high absorption coefficient for infrared radiation. The feasibility of sequential laser-mechanical drilling for a thick CFRP is discussed in this article.

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Composites from carbon fibre reinforced polymers (CFRPs) play a significant role in modern manufacturing. They are typically used in aerospace and other industries that require high strength-to-weight ratios. Composite machining, however, remains a challenging job and sometimes is hampered by poor efficiency.

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Lightweighting is one of the key solutions to reduce the carbon footprint of vehicles. Nowadays, it is still challenging to achieve this target because there is a conflict between the cost and final material performance, as well as the fact that many lightweight solutions are restricted to laboratory or small-scale production. In this work, a commercially feasible strategy was adopted to fabricate materials for lightweight applications.

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The processing and characterization of hybrid PMMA resin composites with nano-zirconia (ZrO2) and electrospun polystyrene (PS) polymer fibers were presented in this study. Reinforcement was selected with the intention to tune the physical and mechanical properties of the hybrid composite. Surface modification of inorganic particles was performed in order to improve the adhesion of reinforcement to the matrix.

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The research presented in this paper investigated the effects of spindle speed and feed rate on the resultant cutting forces (thrust force and torque) and temperatures while drilling SawBones biomechanical test materials and cadaveric cortical bone (bovine and porcine femur) specimens. It also investigated cortical bone anisotropy on the cutting forces, when drilling in axial and radial directions. The cutting forces are only affected by the feed rate, whereas the cutting temperature in contrast is affected by both spindle speed and feed rate.

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Objectives: The purpose of this study was to evaluate efficacy of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and casein phosphopeptide-amorphous calcium fluoride phosphate (CPP-ACFP) containing pastes among individuals with Sjögren's syndrome (SS).

Materials And Methods: Thirty patients were randomised into three groups: CPP-ACP, CPP-ACFP, and 0.05 % NaF to be used two times a day during a 28-day experimental period.

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Purpose: The purpose of the study was to evaluate the surface characteristics of demineralized enamel after treatment with pastes containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) or casein phosphopeptide-amorphous calcium fluoride phosphate (CPP-ACFP) and to compare their efficacy with that of 0.05% NaF.

Methods: Following formation of the artificial carious lesion, enamel slabs were divided into 4 groups (CPP-ACP, CPP-ACFP, 0.

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In the present study, the cells of Bifidobacterium animalis subsp. lactis (BI-01) and Lactobacillus acidophilus (LAC-04) were encapsulated in cocoa butter using spray-chilling technology. Survival assays were conducted to evaluate the resistance of the probiotics to the spray-chilling process, their resistance to the simulated gastric and intestinal fluids (SGF and SIF), and their stability during 90 days of storage.

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Binder-oxidizer interactions in rocket composite propellants can be improved using adequate bonding agents. In the present work, the effectiveness of different 1,3,5-trisubstituted isocyanurates was determined by stereo and metallographic microscopy and using the software package Image-Pro Plus. The chemical analysis of samples was performed by a scanning electron microscope equipped for energy dispersive spectrometry.

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Problem: There is a great need to expand current knowledge of the various functional capacity measurements used in the rehabilitation of chronic low back pain (CLBP) patients. The literature on these patients reports that mobility, endurance, trunk strength and lifting capacity decrease during the process of chronicity. Chronically disabled patients appear to have lower functional capacity than asymptomatic persons.

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20 patients (11 female, 9 male) without low back pain were included in two interrater studies carried out by three physical therapists. The following variables were investigated: shape of the spine, iliac crest heights, twisting of the pelvis, spine test, length of legs, Patrick sign, Schober test, fingertip-to-floor measurements, flexion and extension of the lumbar spine, straight-leg raising, and length of the iliopsoas and the rectus muscles. Intraclass coefficients for the ordinal variables, and kappa coefficients for the nominal variables were calculated for evaluation of interrater agreement.

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It is generally accepted that there are six major groups of living primates: (1) lemurs (including all the primates of Madagascar), (2) lorises (including galago and potto), (3) tarsiers, (4) New World monkeys, (5) Old World monkeys and (6) apes (including man). Tree shrews, once considered to be primates, are now generally recognized as not significantly more closely related to the six groups than other mammals. The first surviving primate lines to diverge from the common primate ancestor are believed to have given rise to one or more of the first three groups.

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Nucleic acid sequences homologous to a single-stranded [(3)H]DNA transcript prepared from a baboon type C virus replicating in dog thymus cells can be readily detected in the cellular DNA of several Old World monkeys (baboon, patas, African green, and two species of macaques-rhesus and stumptail). These results demonstrate that primates other than the baboon also contain endogenous type C viral genes. With the hybridization conditions employed (S(1) nuclease, 65 C), no homologous sequences were detected in DNA from human or New World monkey tissues.

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