Detecting high energy radiation is important to public health, security, nuclear medicine, and astronomical research. The energy-absorbing materials used in detectors fall into two general categories. The first is highly sensitive, making it useful for safety assessment, but requires expensive and bulky ancillary cooling systems which also compromise portability. Other commonly used materials are much more economical to synthesize and operate, and are compact, but sacrifice much in the way of signal sensitivity. There is thus a need for a method to synthesize new materials that combine the best of these two groups; high sensitivity with good energy resolution and low fabrication cost. A composite material containing an inorganic high-Z compound and a polymer would fulfill all of these criteria.       (more...)

Chemically bonded ceramics (CBCs) combine high mechanical strength with corrosion resistance and temperature stability. These materials have utility in hazardous waste containment, radiation shielding, bone tissue engineering, and integration into advanced composites, among other applications. Alternative materials suffer from prohibitively expensive manufacturing processes and low compressive strength. There is thus a need for a new, cost-effective method of producing CBCs. Ideally, the method would afford modulation of parameters such as porosity, color, and setting time, depending on the application desired. (more...)

University researchers have developed methods to synthesize structured glassy carbon nanofibers inside the pores of a porous silicon template by carbonization and obtain free-standing nanofiber by dissolution of the porous silicon template. The carbon nanofibers adopt the shape and morphology of the porous silicon template. The carbon/porous silicon composites are robust, surviving repeated thermal and organic vapor adsorption cycles. The carbon nanocasting approach creates surfaces that: (a) have increased affinity for non-polar organic molecules such as toluene, leading to a 10× improvement in the sensitivity of the sensor; (b) have increased surface area relative to the template leading to greater capacity as an adsorbent; (c) are very stable; and, (d) uniformly cover the underlying silicon layer. (more...)

A novel approach to create molds for manufacturing that allows for reusable molds that can be made into any arbitrary shape. (more...)

A method of forming self-healing polymer gels which composition  is inspired by the dopa-containing adhesive protein used by mussels to adhere to inorganic surfaces. These gels present interesting rheological, universal adhesion and self-healing properties. (more...)

(more...)

Method of coating luminescent phosphors, for lighting and display applications, with nanoscale ZNO films using atomic layer deposition (ALD) - for improved efficacy, thermal stability, and lifetime. (more...)

Presented here is the novel mechanical application of adhesive hydrophobic materials to substrates, the patterning of these materials, and the controlled dip-coating of the resulting patterned substrates to allow the control of the spatial and volumetric attributes of liquid droplets. By controlling the speed with which the substrates are dip-coated, and the viscosity of the polymer bath, fine control over the volumes of liquid that are deposited at particular locations on the substrate is obtained. These techniques may be utilized in a variety of applications including microlens arrays, waveguides, bonding, and fluidic handling. (more...)

As part of the Tacky Dot® donation, the University is offering for commercialization an improved method for mounting particles on a substrate having both tacky and non-tacky areas using a direct current potential This invention especially has utility for the handling and transfer of solder balls and other conductive particles to form solder bumps on the contact pads of electronic devices. (more...)

Throughout the world, there is a growing need for energy efficient housing solutions. The need is particularly strong in developing countries located in tropical climates, where the cost of energy used for temperature and humidity control is very high. As these climates are often prone to flooding, there is also a need for low-cost, energy efficient emergency housing. The bulk of energy is spent on compensating for heat and cooling losses that occur through the building envelope � the outer shell of a building that protects the indoor environment. Most current building envelopes have separate controls for environmental flows such as humidity, cooling, and light transmission that lack precision and are difficult to calibrate. Climatic self-regulation of building envelopes that can reduce the need for artificial space conditioning is highly relevant to develop. Through a pioneering interdisciplinary collaboration between bioengineering and architecture, researchers at UC Berkeley developed a new sensor technology for external building membranes that can actively respond to environmental changes, and provide automated control of moisture and temperature. The system for Self-Activated Building Envelope Regulation (SABER) is inspired by new understanding of moisture barrier and heat transfer in plants. SABER utilizes optomechanical and hygrothermal sensor/actuator networks build onto a thin film membrane, which can replace the expensive and large mechanical control systems. (more...)

Technological advancement demands new types of transducer materials that can efficiently sense and convert force and energy form one type to another for signal processing and modulation, switching and actuation, sensing and energy harvesting. It is also desirable to have transducer materials that mimic cylindrical outer hair cells and retinal cells and able to detect and convert signals instantly and reliably with exceptionally high coupling efficiency at reduced size. Nanocomposite materials could provide the necessary advantages, but are difficulty to be synthesized with controlled morphology and interface characteristics. The rod-coil copolymer systems have attracted widespread interest in both fundamental understanding of the thermodynamics that control nanoscale self-assembly in polymers, as well as technological implication associated with the unique characteristics of the novel designed systems. With inception of the responsive polymer system designed by the inventors, for the first time, there are opportunities to design materials without the compromises typically found in conventional composites. The rationally synthesized nanomaterials can be processed in a thin film format, which provides a platform for technology innovation. (more...)

Functionalized membranes and films for robust ion conductivity at elevated temperatures and low humidities. (more...)

An ultrathin silicon nitride membrane has been fabricated and tested to be useable in temperatures in excess of 1000 °C with mass flux rates several orders of magnitude greater than existing technlogies. Pore shape and size are also tunable. (more...)

The most common method for manufacturing polyolefins and their derivatives is by polymerization of olefin monomers with Ziegler-Natta catalysts or by the use of free radical, nucleophilic, or electrophilic initiators. Although one can achieve high molecular weights with these methods, the resulting products are often polydisperse. Many types of polymers are very difficult, if not impossible to manufacture by olefin polymerization. (more...)

Thrombin is an enzyme in the blood that plays a key role in platelet formation during injury. While blood coagulation is essential for a surface wound, platelet activation underlies various pathological situations such as unstable angina pectoris, myocardial infarction and stroke. Thrombin is mediated by protease activated receptor-1 (PAR-1) which is expressed in the nervous system and in platelets. Once activated by thrombin, PAR-1 induces rapid and dramatic changes in cell morphology that is controlled by a series of localized ATP-dependent reactions. (more...)

BRCA2/RAD5 1 interaction is essential for DNA repair mechanisms and play significant role in tumor resistance to irradiation and chemotherapy treatments. Effective strategies to selectively interfere with BRCA2/RAD5 1 interaction in the context of treatment and chemoprevention of neoplastic diseases are described. (more...)

In the past decade, droplets have been intensively used by the industries as an agent for drug preparations, for plastic polymerizations, and chemical processing. Recent advancements in microfluidic droplet technology has enabled the precise sampling and processing of small volumes of fluids (picoliter to femtoliter) by the controlled viscous shearing in microchannels. Microfluidic technologies has transformed droplets to be used as liquid reaction vessels for screening protein crystallization conditions, as micro templates for assisting self-assembling of materials, as molds for curing polymeric micro spheres, and as components for micro electrical actuator. Programmable fluidic assays for sampling glucose concentration of human physiological fluids, DNA analysis, nano particle synthesis machinery have been individually demonstrated using droplet based microfluidic system. However two drawbacks limit the use of these technologies: 1) the generation of satellite droplets have always being a problem limiting the volume and accuracy of the metered fluid sample. 2) Generation of monodispersed droplets smaller than 1?m has been difficult to achieve. The solution to both problem lies in the use of satellite sorting technologies, in which, satellite droplets, the by product of droplet generation can not only be filtered but also simultaneously be used as a production mechanism for nano-particle synthesis. (more...)

Positron emission tomography (PET) is a non-invasive test that helps doctors diagnose abnormalities, determine the extent of disease, prescribe treatment, and track progress. The patient is given a positron-emitting radiopharmaceutical and the PET scan locates and measures radioactivity, thereby distinguishing the "hot spots" for brain activity related to the specific radiotracer. Imaging agents using PET can greatly enhance chances of early diagnosis of Alzheimer's disease, which can then allow patients to obtain the best therapy and most efficient therapeutic drugs early in the disease progression. Development of imaging agents that can detect the senile plaques associated with Alzheimer's disease is currently underway. One major structural class of PET imaging agents recently developed is aminonaphthalene backbones, which has been shown to target the polymeric form of -amyloid peptide that is associated with senile plaques (SP) and bind to neurofibrillary tangles (NFT). This radiofluorinated molecular imaging probe, known as [18F]FDDNP (FDDNP), became the first technique to image plaques and tangles. FDDNP showed specific binding to areas of SPs and NFTs. However, the radiotracer is highly lipophilic (therefore increases nonspecific binding) due to its structure, particularly the naphthalene ring which gives low target to nontarget ratios. This results in poor image quality and makes diagnosis difficult. (more...)

An epidemic of metabolic diseases including type 2 diabetes and obesity is undermining the health of people living in industrialized societies. There is an urgent need to develop innovative therapeutics. (more...)

Molding and casting of parts can be done more simply and economically for parts that are free from undercut features, primarily because a more expensive multi-piece mold must be used for parts with such undercut features. Therefore immediate feedback to the designer about the presence of costly undercuts allows for their early removal in the design process. Without immediate and accurate feedback designers can wind up with high part costs, waste, and a complicated manufacturing process. UC Berkeley researchers have developed a design system, based on a sophisticated new algorithm that allows for very efficient and rapid identification of undercuts in 3D geometric models. The Berkeley system uses graphics acceleration to allow a user to rotate an object, examine the undercuts in real time and accurately identify undercuts on a pixel by pixel basis. The system also highlights the portions of faces, including curved faces, which have undercuts. Early detection and removal of undercuts ensures rapid development of the lowest cost design. The system can also be used as a subroutine in finding whether any under-cut free parting directions exist and for evaluating which is optimal if there are multiple choices. The ability to find the optimal direction along with pixel level accuracy makes the system highly desirable for designers. (more...)

Multi-walled carbon nanotubes have several potential applications in hydrogen storage, supercapacitors, and structural composites. However, most of these applications depend upon a reliable source of high-quality, inexpensive nanomaterials. Current carbon nanotube production methods, which use high-temperature arc-discharge, drive production costs prohibitively high and limit their use to only small-scale applications. (more...)

A novel type of mesoscopically organized inorganic/organic block copolymer composites. (more...)

Materials with a grain size in the nanometer (10-9 m) range have been the focus of considerable research interest, since such materials have been shown to possess useful properties not obtained with larger grain sizes. However, the preparation of these materials has required at least two processing steps, usually involving the preparation of nanometer-sized grains in powder form (either from rapid solidification from vapor phase or mechanical milling of larger-sized grains) followed by the consolidation of such powders into denser materials by rapid sintering. A University of California scientist, in collaboration with an international research team, has invented a one-step method for synthesizing and consolidating dense nanophase materials. In the UC process, the activation of the synthetic reaction and its short duration ensure that grain growth is totally avoided or markedly minimized, while generating a highly consolidated product that does not require sintering. So far, this process has been successfully employed with ceramics, intermetallics, and composite materials ( e.g. MoSi2, FeAl, TiB2-TiN), and appears to be readily extensible to numerous other materials of varying complexity. Thus, commercial applications of this invention may extend to the production of a wide variety of ceramic materials and devices. (more...)

Nanomaterials have a very diverse range of applications. Graphite encapsulated magnetic metal nanoparticles are of interest as magnetic data-storage media. Nanotubes have applications including: improved carbon-carbon composites for strong lightweight components (e.g. airplane skins and golf clubs), nanometer-scale electronic devices, electron guns for flat-screen televisions, and Scanning Tunneling Microscopy (STM) tips. Several synthesis methods are available for multi-walled nanotubes and they can be produced in bulk. However, there are no comparable methods for the bulk synthesis of single-walled nanotubes, which can therefore cost as much as $2000 per gram. (more...)

Transition metal carbides, nitrides and carbonitrides hold considerable commercial interest because of their properties of hardness, corrosion resistance and thermal stability. The manufacture of the whole class of materials has, however, remained cumbersome and costly up to now. The conventional synthesis of Titanium carbonitride involves three steps: Formation of a carbide phase, a nitride phase, and an homogenization of the two conducted at high temperatures over the course of several hours. Materials scientists at the University of California have recently developed a technique for the direct synthesis of titanium carbonitride. Their procedure takes place in a single, rapid step. Under the conditions of the procedure, a 2000 degree Celsius, self-sustaining combustion wave passes through and converts reactants at a velocity of 9 mm per second. Following propagation of the initial wave, the reaction is complete after approximately 1.7 seconds. The synthesis technique has all the attractive features of combustion syntheses in general, including straight-forwardness, high purity of products, and easy applicability to the manufacture of large items. UC investigators have submitted their products to X-ray analysis, and have found that the synthesis converts reactants completely to a single, cubic, NaCl-type crystal phase with lattice parameters of 0.4269-0.4309 nm. No other phases, by-products, or regions of nonhomogeneity appear in the reacted mixtures. The high temperature at which conversion to titanium carbonitride takes place indicates the high thermal stability of this material. A quality that has attracted additional attention to this particular transition-metal carbonitride is the affinity with which it conjugates with nickel. Titanium carbonitride/nickel cermets have the advantages of tungsten carbide/cobalt cermets but are considerably less costly to produce, given the low cost of nickel relative to cobalt. The development of a direct synthesis by UC researchers makes titanium carbonitride the most desirable material of its type. (more...)