Dawid Skrzypczak

Bio: Dawid Skrzypczak is an academic researcher from Wrocław University of Technology. The author has contributed to research in topics: Fertilizer & Medicine. The author has an hindex of 7, co-authored 26 publications receiving 226 citations.

3D printing filament as a second life of waste plastics-a review.

Abstract: In recent times, the issue of plastic recycling has become one of the leading issues of environmental protection and waste management. Polymer materials have been found an application in many areas of daily life and industry. Along with their extended use, the problem of plastic wastes appeared because, after withdrawal from use, they became persistent and noxious wastes. The possibility of reusing polymeric materials gives a possibility of valorization-a second life-and enables effective waste utilization to obtain consumable products. The 3D printing market is a well-growing sector. Printable filaments can be made from a variety of thermoplastic materials, including those from recycling. This paper focuses on a review of the available literature on the production of filaments for 3D printers from recycled polymers as the alternative to present approach of central selective collection of plastics. The possibility of recycling of basic thermoplastic materials and the impact of processing on their physicochemical and mechanical properties were verified (Lanzotti et al. 2019). In addition, commercially available filaments produced from recycled materials and devices which allow self-production of filaments to 3D printing from plastic waste were reviewed.

A transition from conventional irrigation to fertigation with reclaimed wastewater: Prospects and challenges

Abstract: The aim of this review was to discuss the transition from traditional irrigation to fertigation using reclaimed wastewater in countries with moderate climate. In most European countries there are no regulations on waste water reuse and on the other hand there are countries where regulations are very strict. An important aspect is to standardize the restrictions, which would minimize uncontrolled use of wastewater for fertigation. Wastewater is a source of plant nutrients and organic matter, but can be contaminated with chemicals and pathogens, which in turn can lead to secondary environmental pollution. The reuse of recovered wastewater may require modification of the wastewater treatment process line or construction of stabilization tanks at farms. In both cases, it is necessary to set up initial installations in real systems in order to develop principles for irrigation with reclaimed wastewater for soil and temperate climate conditions. The additional treatment steps required are also associated with large investments, but could reduce fertilization costs and, more importantly, improve the environmental situation. The current scale of fertilizer application does not allow conventional fertilization to fulfill global demand. The introduction of such a solution is a step towards the practical application of circular economy and sustainable crop production. The paper discusses a challenges related with implementation of transition from conventional irrigation to fertigation with reclaimed wastewater in moderate climate countries. A special focus to providing fertilizer nutrients in terms of required doses was undertaken.

Additive manufacturing

Abstract: Propulsion system development requires new, more affordable manufacturing techniques and technologies in a constrained budget environment, while future in-space applications will require in-space manufacturing and assembly of parts and systems. Marshall is advancing cuttingedge commercial capabilities in additive and digital manufacturing and applying them to aerospace challenges. The Center is developing the standards by which new manufacturing processes and parts will be tested and qualified. Rapidly evolving digital tools, such as additive manufacturing, are the leading edge of a revolution in the design and manufacture of space systems that enables rapid prototyping and reduces production times. Marshall has unique expertise in leveraging new digital tools, 3D printing, and other advanced manufacturing technologies and applying them to propulsion systems design and other aerospace materials to meet NASA mission and industry needs. Marshall is helping establish the standards and qualifications “from art to part” for the use of these advanced techniques and the parts produced using them in aerospace or elsewhere in the U.S. industrial base.

Hybrid threshold adaptable quantum secret sharing scheme with reverse Huffman-Fibonacci-tree coding

Abstract: With prevalent attacks in communication, sharing a secret between communicating parties is an ongoing challenge. Moreover, it is important to integrate quantum solutions with classical secret sharing schemes with low computational cost for the real world use. This paper proposes a novel hybrid threshold adaptable quantum secret sharing scheme, using an m-bonacci orbital angular momentum (OAM) pump, Lagrange interpolation polynomials, and reverse Huffman-Fibonacci-tree coding. To be exact, we employ entangled states prepared by m -bonacci sequences to detect eavesdropping. Meanwhile, we encode m -bonacci sequences in Lagrange interpolation polynomials to generate the shares of a secret with reverse Huffman-Fibonacci-tree coding. The advantages of the proposed scheme is that it can detect eavesdropping without joint quantum operations, and permits secret sharing for an arbitrary but no less than threshold-value number of classical participants with much lower bandwidth. Also, in comparison with existing quantum secret sharing schemes, it still works when there are dynamic changes, such as the unavailability of some quantum channel, the arrival of new participants and the departure of participants. Finally, we provide security analysis of the new hybrid quantum secret sharing scheme and discuss its useful features for modern applications.