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Calcium Carbonate: Carbonic acid calcium salt (CaCO3). An odorless, tasteless powder or crystal that occurs in nature. It is used therapeutically as a phosphate buffer in hemodialysis patients and as a calcium supplement.

Determining the Solubility Rules of Ionic Compounds

JoVE 10197

Source: Laboratory of Dr. Neal Abrams — SUNY College of Environmental Science and Forestry

An ionic compound's solubility can be determined via qualitative analysis. Qualitative analysis is a branch of analytical chemistry that uses chemical properties and reactions to identify the cation or anion present in a chemical compound. While the chemical reactions rely on known solubility rules, those same rules can be determined by identifying the products that form. Qualitative analysis is not typically done in modern industrial chemistry labs, but it can be used easily in the field without the need of sophisticated instrumentation. Qualitative analysis also focuses on understanding ionic and net ionic reactions as well as organizing data into a flow chart to explain observations and make definitive conclusions. Many cations have similar chemical properties, as do the anion counterparts. Correct identification requires careful separation and analysis to systematically identify the ions present in a solution. It is important to understand acid/base properties, ionic equilibria, redox reactions, and pH properties to identify ions successfully. While there is a qualitative test for virtually every elemental and polyatomic ion, the identification process typically begi

 General Chemistry

Using Differential Scanning Calorimetry to Measure Changes in Enthalpy

JoVE 5559

Source: Laboratory of Dr. Terry Tritt — Clemson University

Differential Scanning Calorimetry (DSC) is a method of thermodynamic analysis based on heat-flux method, wherein a sample material (enclosed in a pan) and an empty reference pan are subjected to identical temperature conditions. The energy difference that is required to maintain both the pans at the same temperature, owing to the difference in the heat capacities of the sample and the reference pan, is recorded as a function of temperature. This energy released or absorbed is a measure of the enthalpy change (ΔΗ) of the sample with respect to the reference pan.

 General Chemistry

Separation of Mixtures via Precipitation

JoVE 5558

Source: Laboratory of Dr. Ana J. García-Sáez — University of Tübingen

Most samples of interest are mixtures of many different components. Sample preparation, a key step in the analytical process, removes interferences that may affect the analysis. As such, developing separation techniques is an important endeavor not just in academia, but also in industry.  One way to separate mixtures is to use their solubility properties. In this short paper, we will deal with aqueous solutions. The solubility of a compound of interest depends on (1) ionic strength of solution, (2) pH, and (3) temperature. By manipulating with these three factors, a condition in which the compound is insoluble can be used to remove the compound of interest from the rest of the sample.1

 Organic Chemistry

Development of the Chick

JoVE 5155

The chicken embryo (Gallus gallus domesticus) provides an economical and accessible model for developmental biology research. Chicks develop rapidly and are amenable to genetic and physiological manipulations, allowing researchers to investigate developmental pathways down to the cell and molecular levels.

This video review of chick development begins by describing the process of egg fertilization and formation within the chicken reproductive tract. Next, the most commonly used chick staging nomenclature, the Hamburger Hamilton staging series, is introduced. Major events in chick development are then outlined, including the dramatic cellular movements known as gastrulation that form the three major cell layers: The ectoderm, mesoderm, and endoderm. Cells from these layers go on to generate all the tissues within the organism, as well as extraembryonic membranes, which are necessary for the transport of gases, nutrients, and wastes within the eggshell. To conclude the discussion, some exciting techniques will be presented as strategies for studying chick development in greater detail.

 Biology II

Differential Scanning Calorimetry

JoVE 10487

Source: Danielle N. Beatty and Taylor D. Sparks, Department of Materials Science and Engineering, The University of Utah, Salt Lake City, UT

Differential scanning calorimetry (DSC) is an important measurement to characterize thermal properties of materials. DSC is used primarily to calculate the amount of heat stored in a material as it heats up (heat capacity) as well as the heat absorbed or released during chemical reactions or phase changes. However, measurement of this heat can also lead to the calculation of other important properties such as glassy transition temperature, polymer crystallinity, and more. Due to the long, chain-like nature of polymers it is not uncommon for polymer strands to be entangled and disordered. As a result, most polymers are only partially crystalline with the remainder of the polymer being amorphous. In this experiment we will utilize DSC to determine polymer crystallinity.

 Materials Engineering

Safe Handling of Mineral Acids

JoVE 10370

Source: Robert M. Rioux & Taslima A. Zaman, Pennsylvania State University, University Park, PA

A mineral acid (or inorganic acid) is defined as a water-soluble acid derived from inorganic minerals by chemical reaction as opposed to organic acids (e.g. acetic acid, formic acid). Examples of mineral acids include: • Boric acid (CAS No.10043-35-3) • Chromic acid (CAS No.1333-82-0) • Hydrochloric acid (CAS No.7647-01-0) • Hydrofluoric acid (CAS No. 7664-39-3) • Nitric acid (CAS No. 7697-37-2) • Perchloric acid (CAS No. 7601-90-3) • Phosphoric acid (CAS No.7664-38-2) • Sulfuric acid (CAS No.7664-93-9) Mineral acids are commonly found in research laboratories and their corrosive nature makes them a significant safety risk. Since they are important reagents in the research laboratory and often do not have substitutes, it is important that they are handled properly and with care. Some acids are even shock sensitive and under certain conditions may cause explosions (i.e., salts of perchloric acid).

 Lab Safety

Characterization of Calcification Events Using Live Optical and Electron Microscopy Techniques in a Marine Tubeworm

1Department of Biological Sciences, Clemson University, 2Department of Marine Biodiversity Research (BioDive), Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 3Advanced Material Research Laboratory (AMRL), Clemson University, 4Swire Institute of Marine Sciences and School of Biological Sciences, The University of Hong Kong

JoVE 55164


Tension Test of Fiber-Reinforced Polymeric Materials

JoVE 10417

Source: Roberto Leon, Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA

Fiber-reinforced polymeric materials (FRP) are composite materials that are formed by longitudinal fibers embedded in a polymeric resin, thereby creating a polymer matrix with aligned fibers along one or more directions. In its simplest form, the fibers in FRP materials are aligned in an orderly, parallel fashion, thus imparting orthotropic material characteristics, meaning that the material will behave differently in the two directions. Parallel to the fibers, the material will be very strong and/or stiff, whereas perpendicular to the fibers will be very weak, as the strength can only be attributed to the resin instead of the whole matrix. An example of this unidirectional configuration is the commercially available FRP reinforcing bars, which mimic the conventional steel bars used in reinforced concrete construction. FRP materials are used both as stand-alone structures such as pedestrian bridges and staircases, and also as materials to strengthen and repair existing structures. The thin, long plates are often epoxied to existing concrete structures to add strength. In this case, the FRP bars act as external reinforcement. The FRP bars and plates are ligh

 Structural Engineering

Fluorescence Biomembrane Force Probe: Concurrent Quantitation of Receptor-ligand Kinetics and Binding-induced Intracellular Signaling on a Single Cell

1Woodruff School of Mechanical Engineering, Petit Institute for Bioengineering and Biosciences, Georgia Institute of Technology, 2Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 3Charles Perkins Centre, The University of Sydney, 4Institute of Biophysics, Laboratory of RNA Biology, Chinese Academy of Sciences, 5University of Chinese Academy of Sciences, 6School of Medicine and Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University

JoVE 52975


An Overview of Alkenone Biomarker Analysis for Paleothermometry

JoVE 10219

Source: Laboratory of Jeff Salacup - University of Massachusetts Amherst

Throughout this series of videos, natural samples were extracted and purified in search of organic compounds, called biomarkers, that can relate information on climates and environments of the past. One of the samples analyzed was sediment. Sediments accumulate over geologic time in basins, depressions in the Earth into which sediment flows through the action of fluid (water or air), movement, and gravity. Two main types of basins exist, marine (oceans and seas) and lacustrine (lakes). As one might guess, very different types of life live in these settings, driven in large part by the difference in salinity between them. Over the last few decades, organic geochemists discovered a toolbox of biomarker proxies, or compounds that can be used to describe climate or environment, some of which work in marine environments and some of which work in lacustrine. We turn our attention here to the marine realm and alkenone paleothermometry using the Uk'37 sea surface temperature proxy. The most well-established and widely applied open-ocean biomarker sea surface temperature (SST) proxy is Uk'37. Uk'37 = (C37:2) / (C37:2 + C37:

 Earth Science

Removal of Trace Elements by Cupric Oxide Nanoparticles from Uranium In Situ Recovery Bleed Water and Its Effect on Cell Viability

1Division of Physical Therapy, Department of Orthopedics & Rehabilitation, University of New Mexico, 2Department of Ecosystem Science and Management, University of Wyoming, 3School of Pharmacy, University of Wyoming, 4Department of Environmental and Radiological Health Sciences, Colorado State University, 5Center for Environmental Medicine, Colorado State University, 6College of Pharmacy, California Northstate University

JoVE 52715


Antigenic Liposomes for Generation of Disease-specific Antibodies

1Janssen R&D, 2Department of Microbiology and Immunology, University of North Carolina, 3UNC Food Allergy Initiative, University of North Carolina, 4Department of Pediatrics, University of North Carolina, 5Department of Chemistry, University of Alberta, 6Department of Molecular Medicine, Scripps Research Institute, 7Department of Medical Microbiology and Immunology, University of Alberta

Video Coming Soon

JoVE 58285

 JoVE In-Press

Measurement of Maximum Isometric Force Generated by Permeabilized Skeletal Muscle Fibers

1Department of Orthopaedic Surgery, University of Michigan Medical School, 2Department of Molecular & Integrative Physiology, University of Michigan Medical School, 3Department of Biomedical Engineering, University of Michigan Medical School, 4Department of Surgery, Section of Plastic Surgery, University of Michigan Medical School

JoVE 52695


From a 2DE-Gel Spot to Protein Function: Lesson Learned From HS1 in Chronic Lymphocytic Leukemia

1Division of Molecular Oncology, IRCCS, San Raffaele Scientific Institute, 2Department of Haemato-Oncology, King's College London, 3IFOM, FIRC Institute of Molecular Oncology, 4Università Vita-Salute San Raffaele

JoVE 51942


Simple and Effective Administration and Visualization of Microparticles in the Circulatory System of Small Fishes Using Kidney Injection

1Institute of Biology at Irkutsk State University, 2Institute of Biology at Karelian Research Centre of Russian Academy of Sciences, 3Baikal Research Centre, 4Institute of Materials Research and Engineering, Agency for Science, Technology, and Research (A*STAR), 5University of Oulu, Optoelectronics and Measurement Techniques Laboratory

JoVE 57491


Synthesis of Functionalized 10-nm Polymer-coated Gold Particles for Endothelium Targeting and Drug Delivery

1Department of Chemical Engineering, Northeastern University, 2Nanomedicine Science and Technology Center, Northeastern University, 3Department of Physics, Northeastern University, 4Departments of Bioengineering, Northeastern University, 5Department of Neuroscience, Albert Einstein College of Medicine

JoVE 56760


Techniques of Sleeve Gastrectomy and Modified Roux-en-Y Gastric Bypass in Mice

1l'Institut du Thorax, INSERM, CNRS, UNIV Nantes, 2CHU Nantes, Institut des Maladies de l'Appareil Digestif, INSERM U913, 3l'Institut du Thorax, INSERM, CNRS, UNIV Nantes, CHU Nantes, 4Service de Clinique Chirurgicale Digestive et Endocrinienne, CHU de Nantes

JoVE 54905


Two-way Valorization of Blast Furnace Slag: Synthesis of Precipitated Calcium Carbonate and Zeolitic Heavy Metal Adsorbent

1Department of Offshore, Process and Energy Engineering, Cranfield University, 2School of Applied Chemical and Environmental Sciences, Sheridan College Institute of Technology and Advanced Learning, 3School of Engineering, University of Guelph, 4Carbon Systems Engineering, Centre for Combustion, Carbon Capture and Storage, Cranfield University

JoVE 55062


Multi-analyte Biochip (MAB) Based on All-solid-state Ion-selective Electrodes (ASSISE) for Physiological Research

1Department of Agricultural and Biological Engineering, Birck-Bindley Physiological Sensing Facility, Purdue University, 2NASA Ames Research Center, 3Department of Chemistry, Pennsylvania State University Hazleton, 4Cooley LLP, 5NASA Life and Physical Sciences, Human Exploration and Operations Mission Directorate, NASA Headquarters

JoVE 50020


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